Time, Rate, and Distance

106 soru

Soru 81Soru →

A courier drives from a dispatch center to a client's location 6060 miles away and then returns to the dispatch center along the exact same route. The outbound drive to the client takes exactly 22 hours. If the courier's average speed for the entire round trip is 2424 miles per hour, what is the courier's average speed on the return trip?

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Cevap: 2020 miles per hour

Cevap

The courier's average speed on the return trip is 2020 miles per hour.
To find the return speed, we first determine the total time of the trip. The total round-trip distance is 120120 miles (6060 miles each way). Using the overall average speed of 2424 mph, the total time is 120÷24=5120 \div 24 = 5 hours. Since the outbound trip took 22 hours, the return trip must have taken 5−2=35 - 2 = 3 hours. Finally, the return speed is the return distance (6060 miles) divided by the return time (33 hours), which equals 2020 miles per hour.

Adım Adım Çözüm

1
Calculate the total round-trip distance.
Total distance = 60×2=12060 \times 2 = 120 miles.
The one-way distance is 6060 miles, so the round trip is twice that amount.
2
Determine the total time taken for the entire round trip.
Total time = 120 miles÷24 mph=5120 \text{ miles} \div 24 \text{ mph} = 5 hours.
Average speed for the entire trip is total distance divided by total time.
3
Calculate the time taken for the return leg.
Return time = 5 hours−2 hours=35 \text{ hours} - 2 \text{ hours} = 3 hours.
The total trip time minus the outbound time gives the time remaining for the return trip.
4
Calculate the average speed for the return trip.
Return speed = 60 miles÷3 hours=2060 \text{ miles} \div 3 \text{ hours} = 20 miles per hour.
Speed is distance divided by time. The return distance is 6060 miles and the return time is 33 hours.

Anahtar Kavram

Round Trip Average Speed
Soru 82Soru →

A rescue helicopter flies at a rate of 33 miles per minute for 4040 minutes to reach an extraction point. After the pickup, it flies to a hospital at a cruising speed of 120120 miles per hour for 9090 minutes. What is the total distance the helicopter traveled in miles?

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Cevap: 300

Cevap

The correct answer is 300 miles, which is the sum of the 120 miles traveled in the first stage and the 180 miles traveled in the second stage.
The correct answer accurately accounts for the units in both stages of the flight. For the first stage, the units match (miles per minute and minutes), yielding 120 miles. For the second stage, 90 minutes is converted to 1.5 hours to match the miles per hour speed, yielding 180 miles. Adding them together gives 300 miles.

Adım Adım Çözüm

1
Calculate the distance for the first stage by multiplying the rate by the time.
33 miles/minute × 4040 minutes = 120120 miles.
The rate is given in miles per minute and the time is given in minutes, so the units already match and no time conversion is necessary.
2
Convert the time for the second stage from minutes to hours.
9090 minutes ÷ 6060 minutes/hour = 1.51.5 hours.
The cruising speed is given in miles per hour, so the travel time must be converted to hours before calculating distance.
3
Calculate the distance for the second stage using the converted time.
120120 miles/hour × 1.51.5 hours = 180180 miles.
Multiplying the speed in mph by the time in hours yields the distance in miles.
4
Add the distances from both stages to find the total distance traveled.
120120 miles + 180180 miles = 300300 miles.
The total distance of a multi-leg journey is the sum of the distances of each individual leg.

Anahtar Kavram

Calculating multi-leg distances requiring attention to varying speed units and necessary time conversions.
Tahmini Süre:2m 0s
Soru 83Soru →

A ferry transports vehicles from the mainland to an island 1818 miles away. The ferry travels to the island at a speed of 99 miles per hour and returns to the mainland along the same route at a speed of 66 miles per hour.

How many hours does the complete round trip take?

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Cevap: 5

Cevap

The complete round trip takes 5 hours.
The round trip consists of two legs with different speeds. The outbound leg takes 18÷9=218 \div 9 = 2 hours. The return leg takes 18÷6=318 \div 6 = 3 hours. Adding these together yields a total time of 55 hours for the entire trip.

Adım Adım Çözüm

1
Calculate the time taken for the outbound trip.
18÷9=218 \div 9 = 2 hours
Time is equal to distance divided by rate. This gives the time spent traveling to the island.
2
Calculate the time taken for the return trip.
18÷6=318 \div 6 = 3 hours
The return trip covers the same distance but at a slower speed.
3
Calculate the total round-trip time.
2+3=52 + 3 = 5 hours
The total time for a round trip is the sum of the time spent on each individual leg.

Anahtar Kavram

Calculating total round-trip time by finding the time for each leg separately.
Soru 84Soru →

A cyclist travels from her home to a nearby town, a distance of 1515 miles, at an average speed of 1212 mph. On the return trip along the same route, her average speed is 2020 mph. What is her average speed, in mph, for the entire round trip?

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Cevap: 15

Cevap

15
The correct average speed is found by dividing the total round-trip distance (3030 miles) by the total travel time (22 hours), resulting in 1515 mph.

Adım Adım Çözüm

1
Calculate the time for the outbound trip.
1.25 hours
Time equals distance divided by speed (15 miles/12 mph=1.25 hours15 \text{ miles} / 12 \text{ mph} = 1.25 \text{ hours}).
2
Calculate the time for the return trip.
0.75 hours
Time equals distance divided by speed (15 miles/20 mph=0.75 hours15 \text{ miles} / 20 \text{ mph} = 0.75 \text{ hours}).
3
Determine the total time and total distance for the entire round trip.
Total time = 2 hours, Total distance = 30 miles
Adding the outbound and return times (1.25+0.751.25 + 0.75) gives 2 hours. The round trip is twice the one-way distance (15×215 \times 2).
4
Calculate the average speed for the entire round trip.
15 mph
Average speed is total distance divided by total time (30 miles/2 hours=15 mph30 \text{ miles} / 2 \text{ hours} = 15 \text{ mph}).

Anahtar Kavram

Average Speed for a Round Trip
Soru 85Soru →

A logistics convoy leaves a supply depot and travels at a steady speed of 40 miles per hour for 2 hours and 15 minutes. After a 45-minute halt to refuel, the convoy resumes its route at a speed that is 20% faster than its initial speed. It travels at this new speed for 1 hour and 40 minutes until reaching the forward operating base. What is the total distance traveled by the convoy, in miles?

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Cevap: 170; 170 miles; 170 mi

Cevap

170
The correct answer is found by breaking the journey into two separate legs of movement, converting all times to hours, calculating the distance for each leg independently using their respective speeds, and summing the results.

Adım Adım Çözüm

1
Calculate the time traveled during the first leg in hours.
2 hours and 15 minutes is equivalent to 2.25 hours.
Since the speed is given in miles per hour, time must be expressed in hours.
2
Calculate the distance covered during the first leg.
40 mph × 2.25 hours = 90 miles.
Using the distance formula d=r×td = r \times t.
3
Determine the speed of the convoy for the second leg.
40 mph + (0.20 × 40 mph) = 40 + 8 = 48 mph.
The problem states the convoy travels 20% faster after the halt.
4
Calculate the time traveled during the second leg in hours.
1 hour and 40 minutes is equivalent to 140601 \frac{40}{60} hours, which simplifies to 53\frac{5}{3} hours.
Converting mixed time units to a single fraction of hours is necessary for accurate calculation.
5
Calculate the distance covered during the second leg.
48 mph × 53\frac{5}{3} hours = 80 miles.
Using the distance formula d=r×td = r \times t.
6
Calculate the total distance traveled.
90 miles + 80 miles = 170 miles.
The total distance is the sum of the distances from the two active travel legs. The 45-minute halt added 0 miles.

Anahtar Kavram

Calculating distance across multiple legs with varying speeds and mixed time units.
Soru 86Soru →

A pilot flies a cargo plane from Airport A to Airport B at an average speed of 240240 mph. The pilot returns along the exact same route, but due to a strong headwind, the return flight averages only 160160 mph. If the total flying time for the entire round trip was exactly 55 hours, what is the one-way distance between Airport A and Airport B, in miles?

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Cevap: 480

Cevap

480
By setting up an algebraic equation representing the total time taken for both legs of the trip (using Time = Distance / Speed), we get d/240+d/160=5d/240 + d/160 = 5. Solving this equation by finding a common denominator of 480480 yields 5d/480=55d/480 = 5, which simplifies to d=480d = 480 miles.

Adım Adım Çözüm

1
Define a variable for the unknown distance.
Let dd be the one-way distance in miles.
We need to find the one-way distance and relate it to the given times and speeds.
2
Express the time for each leg of the trip using the formula Time = Distance / Speed.
Outbound time = d240\frac{d}{240}, Return time = d160\frac{d}{160}.
The total time is given, so we need mathematical expressions for the time of each individual leg.
3
Set up an equation for the total time.
d240+d160=5\frac{d}{240} + \frac{d}{160} = 5
The sum of the outbound flight time and the return flight time equals the total round-trip flight time.
4
Find a common denominator to add the fractions.
The least common multiple of 240240 and 160160 is 480480. The equation becomes 2d480+3d480=5\frac{2d}{480} + \frac{3d}{480} = 5.
To solve for dd, we must combine the fractional terms into a single term.
5
Solve the equation for dd.
5d480=5⇒5d=2400⇒d=480\frac{5d}{480} = 5 \Rightarrow 5d = 2400 \Rightarrow d = 480.
Isolating dd gives the final one-way distance.

Anahtar Kavram

Solving round trip scenarios by setting up a total time equation: dv1+dv2=ttotal\frac{d}{v_1} + \frac{d}{v_2} = t_{total}
Tahmini Süre:2m 0s
Soru 87Soru →

A cyclist rides from his home to a nearby park 1212 miles away at a speed of 1212 miles per hour. He returns home along the same route at a speed of 66 miles per hour. What is his average speed for the entire round trip in miles per hour?

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Cevap: 88

Cevap

The average speed for the entire round trip is 88 miles per hour.
The correct answer is found by first determining the total distance and total time. The park is 12 miles away, making the round trip 24 miles. The trip there takes 1 hour (12/12) and the trip back takes 2 hours (12/6), for a total of 3 hours. Dividing the total distance (24) by the total time (3) yields an average speed of 8 mph.

Adım Adım Çözüm

1
Calculate the total distance for the round trip.
1212 miles (outbound) + 1212 miles (return) = 2424 total miles.
Average speed requires the total distance traveled over the entire journey.
2
Calculate the time taken for the outbound trip.
1212 miles / 1212 mph = 11 hour.
Time is equal to distance divided by speed.
3
Calculate the time taken for the return trip.
1212 miles / 66 mph = 22 hours.
The cyclist travels the same distance back, but at a slower speed.
4
Calculate the total time for the trip.
11 hour + 22 hours = 33 total hours.
Average speed requires the total duration of the trip.
5
Calculate the average speed for the round trip.
2424 miles / 33 hours = 88 miles per hour.
Average speed is equal to total distance divided by total time.

Anahtar Kavram

Average Speed for Round Trips
Soru 88Soru →

A military cargo plane flies for 22 hours and 2020 minutes at an average speed of 420420 miles per hour. It then encounters a strong headwind, reducing its average speed to 360360 miles per hour for the remaining 4545 minutes of the flight. What is the total distance, in miles, traveled by the cargo plane?

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Cevap: 1250; 1250 miles; 1,250; 1,250 miles

Cevap

The total distance traveled by the cargo plane is 1250 miles.
The problem requires calculating the distance for two separate flight segments and adding them together. For the first segment, the time is 22 hours and 2020 minutes (73\frac{7}{3} hours) and the speed is 420420 mph, resulting in 980980 miles. For the second segment, the time is 4545 minutes (34\frac{3}{4} hours) and the speed is 360360 mph, resulting in 270270 miles. Adding these distances yields a total of 12501250 miles.

Adım Adım Çözüm

1
Convert the flight time of the first leg into hours.
22 hours and 2020 minutes is equal to 2132\frac{1}{3} hours, or 73\frac{7}{3} hours.
Speed is given in miles per hour, so time must be in hours to correctly use the distance formula.
2
Calculate the distance traveled during the first leg.
420×73=980420 \times \frac{7}{3} = 980 miles.
Applying the formula Distance = Rate ×\times Time.
3
Convert the flight time of the second leg into hours.
4545 minutes is equal to 4560\frac{45}{60} hours, which simplifies to 34\frac{3}{4} hours.
Uniform units are required before calculating the distance for the second segment.
4
Calculate the distance traveled during the second leg.
360×34=270360 \times \frac{3}{4} = 270 miles.
Applying the formula Distance = Rate ×\times Time for the reduced speed segment.
5
Add the distances from both legs to find the total distance.
980+270=1250980 + 270 = 1250 miles.
The total distance is the sum of the distances traveled in each individual segment of the flight.

Anahtar Kavram

Calculating total distance for a multi-leg journey by accurately converting minutes to fractional hours and applying the Distance = Rate ×\times Time formula.
Soru 89Soru →

A cargo aircraft flies from a logistics hub to a regional airport, a one-way distance of 360360 miles. The aircraft makes the outbound journey at an average speed of 180180 mph. On the return trip along the exact same route, carrying a heavier load, it travels at an average speed of 120120 mph. What is the aircraft's average speed for the entire round trip?

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Cevap: 144144 mph

Cevap

The correct average speed for the entire round trip is 144144 mph.
The correct average speed is found by dividing the total round-trip distance by the total round-trip time. The total distance is 720720 miles (360360 outbound +360+ 360 return). The outbound flight takes 22 hours (360÷180360 \div 180) and the return flight takes 33 hours (360÷120360 \div 120), resulting in a total time of 55 hours. Dividing 720720 miles by 55 hours gives an average speed of 144144 mph.

Adım Adım Çözüm

1
Calculate the time taken for the outbound journey.
360360 miles ÷180\div 180 mph =2= 2 hours.
Time equals distance divided by speed.
2
Calculate the time taken for the return journey.
360360 miles ÷120\div 120 mph =3= 3 hours.
The return distance is the same, but the return speed is different.
3
Determine the total distance and total time for the entire round trip.
Total distance =360+360=720= 360 + 360 = 720 miles. Total time =2+3=5= 2 + 3 = 5 hours.
Average speed for a multi-leg journey requires the overall totals, not just the averages of each leg.
4
Calculate the overall average speed.
720720 miles ÷5\div 5 hours =144= 144 mph.
Average speed is equal to the total distance divided by the total time.

Anahtar Kavram

Average Speed in Round Trips
Soru 90Soru →

A high-speed passenger train travels between two major cities. It covers the first segment of the journey at an average speed of 120 mph120\text{ mph} for 1 hour and 45 minutes1\text{ hour and } 45\text{ minutes}. Due to track maintenance, it reduces its speed to 40 mph40\text{ mph} for 36 minutes36\text{ minutes}. After clearing the maintenance zone, it accelerates and travels at 150 mph150\text{ mph} for 48 minutes48\text{ minutes} to reach its final destination. What is the total distance of the trip?

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Cevap: 354 miles

Cevap

354 miles
The total distance is found by calculating the distance of each leg separately and adding them together. First, convert all minute values into hours by dividing by 60 (1 hr 45 min=1.75 hr1\text{ hr } 45\text{ min} = 1.75\text{ hr}; 36 min=0.6 hr36\text{ min} = 0.6\text{ hr}; 48 min=0.8 hr48\text{ min} = 0.8\text{ hr}). Then, multiply each time by its corresponding speed to find the distances: 120×1.75=210 miles120 \times 1.75 = 210\text{ miles}; 40×0.6=24 miles40 \times 0.6 = 24\text{ miles}; and 150×0.8=120 miles150 \times 0.8 = 120\text{ miles}. Adding these together gives 210+24+120=354 miles210 + 24 + 120 = 354\text{ miles}.

Adım Adım Çözüm

1
Convert the travel time for the first segment into hours.
45 minutes=4560 hours=0.75 hours45\text{ minutes} = \frac{45}{60}\text{ hours} = 0.75\text{ hours}. Total time =1.75 hours= 1.75\text{ hours}.
Speed is given in miles per hour (mph), so time must be in hours to calculate distance correctly.
2
Calculate the distance covered in the first segment.
Distance =120 mph×1.75 hours=210 miles= 120\text{ mph} \times 1.75\text{ hours} = 210\text{ miles}.
Applying the formula Distance = Rate × Time for the first leg of the journey.
3
Convert the time and calculate the distance for the second (maintenance) segment.
Time =3660 hours=0.6 hours= \frac{36}{60}\text{ hours} = 0.6\text{ hours}. Distance =40 mph×0.6 hours=24 miles= 40\text{ mph} \times 0.6\text{ hours} = 24\text{ miles}.
The second segment has a different speed and time that must be evaluated independently.
4
Convert the time and calculate the distance for the final segment.
Time =4860 hours=0.8 hours= \frac{48}{60}\text{ hours} = 0.8\text{ hours}. Distance =150 mph×0.8 hours=120 miles= 150\text{ mph} \times 0.8\text{ hours} = 120\text{ miles}.
The final segment has its own rate and duration to calculate.
5
Sum the distances of all segments to find the total distance.
210+24+120=354 miles210 + 24 + 120 = 354\text{ miles}.
The total distance of a multi-leg journey is the sum of the distances of the individual legs.

Anahtar Kavram

Calculating distance using mixed time units across multiple journey segments
Soru 91Soru →

A military convoy must complete a 180-mile route to a forward operating base in exactly 4 hours. The convoy travels at an average speed of 50 mph for 90 minutes, then halts for a 60-minute security checkpoint. What average speed, in mph, must the convoy maintain for the remainder of the journey to arrive exactly on time?

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Cevap: 70

Cevap

70
The convoy has already traveled 75 miles in 1.5 hours, and stopped for 1.0 hour. This means 2.5 hours have elapsed in total, leaving 1.5 hours to travel the remaining 105 miles. Dividing 105 miles by 1.5 hours results in a required speed of 70 mph.

Adım Adım Çözüm

1
Convert the travel and checkpoint times from minutes to hours.
90 minutes = 1.5 hours; 60 minutes = 1.0 hour.
Speed is given in miles per hour (mph), so time must be uniformly expressed in hours.
2
Calculate the distance covered during the first leg of the journey.
50 mph × 1.5 hours = 75 miles.
This establishes how much of the 180-mile route has already been completed before the stop.
3
Determine the remaining distance to the base.
180 miles - 75 miles = 105 miles.
This is the distance that must be covered in the final driving leg.
4
Calculate the time remaining to complete the route.
4 hours - (1.5 hours + 1.0 hour) = 4 - 2.5 = 1.5 hours.
The convoy must arrive exactly 4 hours after initial departure, accounting for both active driving and stopped time.
5
Calculate the required average speed for the final leg.
105 miles ÷ 1.5 hours = 70 mph.
Rate equals distance divided by time.

Anahtar Kavram

Calculating Rate and Time
Tahmini Süre:2m 30s
Soru 92Soru →

A medical evacuation helicopter is dispatched from its base camp to pick up a patient at a rural hospital 120120 miles away. The pilot flies to the hospital at a steady speed of 120120 mph. Due to heavy headwinds on the way back, the helicopter's average speed for the entire round trip drops to 8080 mph. What is the helicopter's average speed, in mph, during the return flight?

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Cevap: 60

Cevap

60
By finding the total trip time (3 hours) and subtracting the outbound time (1 hour), we determine the return trip took 2 hours to cover 120 miles. Dividing the 120-mile distance by the 2 hours yields an average return speed of 60 mph.

Adım Adım Çözüm

1
Calculate the total round-trip distance
240 miles
The one-way distance is 120 miles, so the full round trip is 120 + 120 = 240 miles.
2
Determine the total flight time
3 hours
Time equals total distance divided by the overall average speed (240 / 80 = 3).
3
Calculate the time taken for the outbound flight
1 hour
Time equals outbound distance divided by outbound speed (120 / 120 = 1).
4
Find the time taken for the return flight
2 hours
Return time is the total trip time minus the outbound trip time (3 - 1 = 2).
5
Calculate the average speed of the return flight
60 mph
Speed equals return distance divided by return time (120 / 2 = 60).

Anahtar Kavram

Average speed for a round trip is the total distance divided by the total time, not the arithmetic mean of the two different speeds.
Soru 93Soru →

A Coast Guard search-and-rescue aircraft executes a mission over the ocean. It first flies directly to the designated search zone at an average speed of 180 mph180\text{ mph} for 11 hour and 2020 minutes. Once inside the zone, it slows to a search speed of 120 mph120\text{ mph}, flying a grid pattern for 22 hours and 1515 minutes. After completing the grid, it returns to base along a direct route at 150 mph150\text{ mph} for 4848 minutes. What is the total distance flown by the aircraft during the entire mission, in miles?

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Cevap: 630

Cevap

630
The correct total distance is 630 miles. This is found by carefully converting the travel times of all three mission legs into hours, calculating the distance for each leg using the formula Distance = Rate × Time, and then summing the three results together.

Adım Adım Çözüm

1
Calculate the distance flown to reach the search zone.
180 mph * (4/3) hours = 240 miles.
Converting 1 hour and 20 minutes to 1.333... (or 4/3) hours is required to match the speed unit (mph).
2
Calculate the distance flown while searching the grid.
120 mph * 2.25 hours = 270 miles.
Converting 2 hours and 15 minutes to 2.25 hours is required to match the speed unit (mph).
3
Calculate the distance flown to return to base.
150 mph * 0.8 hours = 120 miles.
Converting 48 minutes to 48/60 or 0.8 hours is required to match the speed unit (mph).
4
Sum the distances from all three legs of the mission.
240 + 270 + 120 = 630 miles.
The total distance is the sum of the individual leg distances.

Anahtar Kavram

Calculating distance for multiple travel segments by independently converting mixed time units into hours and applying the Distance = Rate × Time formula.
Tahmini Süre:2m 30s
Soru 94Soru →

A military cargo aircraft flies from Base Alpha to Base Bravo at an average speed of 300300 miles per hour. Upon arrival, the aircraft spends exactly 11 hour and 3030 minutes on the ground being loaded. It then returns to Base Alpha along the exact same route at an average speed of 600600 miles per hour. If the total elapsed time for the entire mission, from the initial departure to the final return, was 77 hours and 3030 minutes, what was the aircraft's overall average speed, in miles per hour, for the entire mission?

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Cevap: 320

Cevap

The aircraft's overall average speed for the entire mission was 320320 miles per hour.
The correct overall average speed is found by first calculating the total distance traveled, and then dividing it by the total elapsed time for the mission. By subtracting the 1.51.5-hour ground delay from the 7.57.5-hour total time, we find the aircraft flew for a total of 66 hours. Using the relationship D300+D600=6\frac{D}{300} + \frac{D}{600} = 6, we find the one-way distance DD is 12001200 miles. Therefore, the total round-trip distance is 24002400 miles. Dividing the 24002400 miles by the total mission time of 7.57.5 hours yields an overall average speed of 320320 mph.

Adım Adım Çözüm

1
Determine the actual time the aircraft spent flying.
77 hours and 3030 minutes total minus 11 hour and 3030 minutes on the ground equals 66 hours of flight time.
The total elapsed time includes the ground time, which must be subtracted to isolate the time spent traveling at the given speeds.
2
Set up an equation to find the one-way distance between the bases.
Let DD be the one-way distance. D300+D600=6\frac{D}{300} + \frac{D}{600} = 6
Time equals distance divided by rate. The sum of the time for the outbound flight and the return flight equals the total flight time.
3
Solve the equation for the one-way distance (DD).
D=1200D = 1200 miles
2D600+D600=6⇒3D600=6⇒D200=6⇒D=1200\frac{2D}{600} + \frac{D}{600} = 6 \Rightarrow \frac{3D}{600} = 6 \Rightarrow \frac{D}{200} = 6 \Rightarrow D = 1200.
4
Calculate the total distance traveled during the entire mission.
1200×2=24001200 \times 2 = 2400 miles
The mission is a round trip, so the one-way distance must be doubled.
5
Calculate the overall average speed for the entire mission.
2400÷7.5=3202400 \div 7.5 = 320 miles per hour.
Overall average speed equals total distance divided by total elapsed time (which includes the ground delay).

Anahtar Kavram

Overall average speed is the total distance traveled divided by the total elapsed time, which includes any stationary delays. It cannot be calculated by simply averaging the individual speeds.

Alternatif Yöntem

Instead of solving for distance first, you can use the harmonic mean of the speeds to find the average speed while in the air: 2×300×600300+600=400 mph\frac{2 \times 300 \times 600}{300 + 600} = 400 \text{ mph}. The aircraft flew for 66 hours at an average of 400 mph400 \text{ mph}, covering 24002400 miles. Then, divide 24002400 miles by the total mission time (7.57.5 hours) to find the overall average speed: 320 mph320 \text{ mph}.
Tahmini Süre:3m 0s
Soru 95Soru →

A mountain rescue snowmobile is dispatched to retrieve a stranded hiker. It travels from base camp to the hiker's location at an average speed of 3030 miles per hour. Carrying the extra passenger on the return trip, the snowmobile heads back along the exact same trail at an average speed of 2020 miles per hour. If the total driving time for the entire rescue mission is 9090 minutes, what is the total round-trip distance traveled by the snowmobile?

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Cevap: 3636 miles

Cevap

The total round-trip distance is 3636 miles.
To find the total distance, we must use the relationship between distance, rate, and time. Because the one-way distances are equal, we can represent the one-way distance as dd. The time for the outbound trip is d30\frac{d}{30} and the return trip is d20\frac{d}{20}. Their sum equals the total time of 1.51.5 hours (since 9090 minutes is 1.51.5 hours). Solving d30+d20=1.5\frac{d}{30} + \frac{d}{20} = 1.5 yields d=18d = 18. The round-trip distance is 2d2d, which is 3636 miles.

Adım Adım Çözüm

1
Convert the total driving time from minutes to hours.
90 minutes=1.5 hours90 \text{ minutes} = 1.5 \text{ hours}
Speed is given in miles per hour, so time must be consistent with these units.
2
Set up an equation representing the total time using the formula Time=DistanceRate\text{Time} = \frac{\text{Distance}}{\text{Rate}}. Let dd represent the one-way distance.
d30+d20=1.5\frac{d}{30} + \frac{d}{20} = 1.5
The total time is the sum of the time taken for the outbound trip and the time taken for the return trip.
3
Solve for the one-way distance (dd) by finding a common denominator.
2d60+3d60=1.5⇒5d60=1.5⇒d12=1.5⇒d=18 miles\frac{2d}{60} + \frac{3d}{60} = 1.5 \Rightarrow \frac{5d}{60} = 1.5 \Rightarrow \frac{d}{12} = 1.5 \Rightarrow d = 18 \text{ miles}
Solving the equation provides the distance for a single leg of the journey.
4
Calculate the total round-trip distance by multiplying the one-way distance by 2.
18×2=36 miles18 \times 2 = 36 \text{ miles}
The question asks for the total round-trip distance, which includes both the outbound and return legs.

Anahtar Kavram

Calculating distance for a round trip involving different speeds by setting up a total time equation.
Soru 96Soru →

A rescue helicopter departs base at 09150915 hours for a distress signal 120120 miles away. It flies outbound at 160160 mph, spends 3030 minutes on scene, and returns along the same route at 120120 mph. At what time does the helicopter arrive back at the base?

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Cevap: 1130 hours

Cevap

1130 hours
The correct arrival time is found by determining the time for each flight leg individually (Distance / Rate), ensuring decimal hours are correctly converted into minutes, adding the on-scene time, and then adding that total elapsed duration to the initial departure time.

Adım Adım Çözüm

1
Calculate the duration of the outbound flight.
0.750.75 hours (or 4545 minutes)
Using the formula Time=DistanceRate\text{Time} = \frac{\text{Distance}}{\text{Rate}}, the outbound flight takes 120160=0.75\frac{120}{160} = 0.75 hours. To convert to minutes, multiply by 6060: 0.75×60=450.75 \times 60 = 45 minutes.
2
Calculate the duration of the return flight.
11 hour (or 6060 minutes)
The helicopter returns along the same 120120-mile route at a speed of 120120 mph. 120120=1\frac{120}{120} = 1 hour.
3
Calculate the total mission duration.
135135 minutes (or 22 hours 1515 minutes)
Sum the three segments of the mission: Outbound (4545 minutes) + On-scene (3030 minutes) + Return (6060 minutes) = 135135 minutes total.
4
Determine the final arrival time based on the departure time.
11301130 hours
Add the total duration of 22 hours and 1515 minutes to the departure time of 09150915 hours. 0915+2 hours 15 minutes=11300915 + 2\text{ hours } 15\text{ minutes} = 1130 hours.

Anahtar Kavram

Calculating elapsed time using the relationship between distance and rate, converting decimal hours to minutes, and correctly summing components of a multi-leg journey.
Soru 97Soru →

A military convoy is traveling along a straight highway at a constant speed of 45 miles per hour45\text{ miles per hour}. A scout vehicle leaves the rear of the convoy and travels forward to reach the front of the convoy. The total length of the convoy is 1.5 miles1.5\text{ miles}, and the scout vehicle travels at a constant speed of 88 feet per second88\text{ feet per second}. How many minutes does it take for the scout vehicle to reach the front of the convoy? (1 mile=5,280 feet1\text{ mile} = 5,280\text{ feet})

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Cevap: 6

Cevap

6
The correct answer is found by equalizing the speed units and analyzing relative motion. First, converting the scout's speed gives 88 ft/s×(3600/5280)=60 mph88\text{ ft/s} \times (3600 / 5280) = 60\text{ mph}. Because the convoy is also moving forward at 45 mph45\text{ mph}, the relative closing speed is 60 mph−45 mph=15 mph60\text{ mph} - 45\text{ mph} = 15\text{ mph}. The scout needs to cover the 1.5 mile1.5\text{ mile} length of the convoy, which takes 1.5 miles/15 mph=0.1 hours1.5\text{ miles} / 15\text{ mph} = 0.1\text{ hours}. Finally, converting this to minutes yields 0.1×60=6 minutes0.1 \times 60 = 6\text{ minutes}.

Adım Adım Çözüm

1
Convert the scout vehicle's speed from feet per second to miles per hour.
88 ft/s×3,600 s1 hr÷5,280 ft1 mile=60 mph88\text{ ft/s} \times \frac{3,600\text{ s}}{1\text{ hr}} \div \frac{5,280\text{ ft}}{1\text{ mile}} = 60\text{ mph}.
To establish a common unit of speed for both vehicles before calculating relative motion.
2
Calculate the relative speed of the scout vehicle compared to the convoy.
60 mph−45 mph=15 mph60\text{ mph} - 45\text{ mph} = 15\text{ mph}.
Because both vehicles are moving in the same direction, subtracting the convoy's speed from the scout's speed gives the actual rate at which the scout is catching up (closing speed).
3
Determine the time required to cover the distance of the convoy in hours.
Time = Distance / Rate = 1.5 miles/15 mph=0.1 hours1.5\text{ miles} / 15\text{ mph} = 0.1\text{ hours}.
Applying the time, rate, and distance formula using the length of the convoy and the relative closing speed.
4
Convert the time from hours to minutes.
0.1 hours×60 minutes/hour=6 minutes0.1\text{ hours} \times 60\text{ minutes/hour} = 6\text{ minutes}.
The question explicitly asks for the answer in minutes.

Anahtar Kavram

Relative Motion and Unit Conversions

Alternatif Yöntem

Instead of converting everything to miles and hours, you can convert everything to feet and seconds. Convoy speed = 45 mph×(5280/3600)=66 ft/s45\text{ mph} \times (5280 / 3600) = 66\text{ ft/s}. Relative speed = 88 ft/s−66 ft/s=22 ft/s88\text{ ft/s} - 66\text{ ft/s} = 22\text{ ft/s}. Distance = 1.5 miles×5280=7,920 feet1.5\text{ miles} \times 5280 = 7,920\text{ feet}. Time = 7,920 ft/22 ft/s=360 seconds7,920\text{ ft} / 22\text{ ft/s} = 360\text{ seconds}. Finally, 360 seconds/60 seconds/minute=6 minutes360\text{ seconds} / 60\text{ seconds/minute} = 6\text{ minutes}.
Tahmini Süre:3m 0s
Soru 98Soru →

A supply train needs to deliver equipment to a base that is 110 miles away. For the first 1 hour and 20 minutes, the train travels at a steady rate of 30 mph. Due to track repairs, the train must travel at exactly 20 mph for the remainder of the trip. What is the total travel time from the start of the journey until the train arrives at the base?

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Cevap: 4 hours and 50 minutes

Cevap

The total travel time is 4 hours and 50 minutes.
The correct answer is found by first determining that the train travels 40 miles during its initial 1 hour and 20 minutes (30 mph×113 hours30 \text{ mph} \times 1 \frac{1}{3} \text{ hours}). With 70 miles remaining from the 110-mile total (110−40110 - 40), traveling at 20 mph takes exactly 3.5 hours, or 3 hours and 30 minutes. Adding the duration of both legs (1 hour 20 minutes+3 hours 30 minutes1 \text{ hour } 20 \text{ minutes} + 3 \text{ hours } 30 \text{ minutes}) results in a total travel time of 4 hours and 50 minutes.

Adım Adım Çözüm

1
Calculate the distance covered in the first leg of the journey.
The train travels 40 miles in the first leg.
Since 1 hour and 20 minutes is equivalent to 1131 \frac{1}{3} hours (or 43\frac{4}{3} hours), multiplying the rate of 30 mph by this time gives 30×43=4030 \times \frac{4}{3} = 40 miles.
2
Determine the remaining distance to the base.
There are 70 miles remaining.
Subtracting the distance covered from the total distance (110−40=70110 - 40 = 70) gives the remaining travel distance.
3
Calculate the time required for the second leg of the journey.
The second leg takes 3 hours and 30 minutes.
Dividing the remaining distance by the new speed (70÷2070 \div 20) results in 3.5 hours, which equals 3 hours and 30 minutes.
4
Add the time of both legs to find the total travel time.
The total travel time is 4 hours and 50 minutes.
Adding the initial 1 hour and 20 minutes to the second leg's 3 hours and 30 minutes gives 4 hours and 50 minutes.

Anahtar Kavram

Calculating total elapsed time for multi-leg journeys by tracking distance and converting time units properly.
Soru 99Soru →

A military convoy must travel a total distance of 540540 miles to reach a forward operating base. To ensure they arrive on schedule, they need to maintain an overall average speed of 4545 miles per hour for the entire journey.

During the first segment, they travel 150150 miles in exactly 150150 minutes. During the second segment, they travel 135135 miles at an average speed of 3030 miles per hour.

What average speed, in miles per hour, must the convoy maintain for the remainder of the trip to meet their target overall average speed?

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Cevap: 51

Cevap

The convoy must maintain a speed of 51 mph for the remainder of the trip.
To find the required speed for the remainder of the trip, you must determine how much distance is left and how much time remains. First, calculate the total time allowed for the trip: 540 miles÷45 mph=12 hours540 \text{ miles} \div 45 \text{ mph} = 12 \text{ hours}. The first segment takes 150 minutes÷60=2.5 hours150 \text{ minutes} \div 60 = 2.5 \text{ hours} to cover 150150 miles. The second segment takes 135 miles÷30 mph=4.5 hours135 \text{ miles} \div 30 \text{ mph} = 4.5 \text{ hours}. The total distance covered so far is 285285 miles (150+135150 + 135) over a total of 77 hours (2.5+4.52.5 + 4.5). This leaves 255255 miles (540−285540 - 285) to be covered in the remaining 55 hours (12−712 - 7). Dividing the remaining distance by the remaining time (255÷5255 \div 5) results in a required speed of 5151 mph.

Adım Adım Çözüm

1
Calculate the total allowable time for the entire journey.
1212 hours
Total time is found by dividing the total distance (540540 miles) by the overall target average speed (4545 mph).
2
Convert the duration of the first segment into hours.
2.52.5 hours
To maintain consistent units, divide the given 150150 minutes by 6060 minutes per hour.
3
Calculate the time required for the second segment.
4.54.5 hours
Time equals distance divided by speed (135 miles÷30 mph135 \text{ miles} \div 30 \text{ mph}).
4
Determine the remaining distance and remaining time for the final segment.
Remaining distance: 255255 miles. Remaining time: 55 hours.
Subtract the completed distances (150+135=285150 + 135 = 285) from 540540, and subtract the used time (2.5+4.5=72.5 + 4.5 = 7) from 1212.
5
Calculate the required average speed for the final segment.
5151 miles per hour
Average speed equals remaining distance divided by remaining time (255÷5255 \div 5).

Anahtar Kavram

Average speed over multiple segments requires calculating total distance and total time, rather than taking the arithmetic mean of individual segment speeds.
Tahmini Süre:2m 0s
Soru 100Soru →

A reconnaissance patrol must complete a 2424-mile route with an overall average speed of 44 mph to meet their extraction window. For the first 1010 miles, difficult terrain limits their average speed to 55 mph. After completing this section, the patrol halts for exactly 120120 minutes to observe an objective. To achieve the required overall average speed, what must be their average speed, in mph, for the remaining distance?

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Cevap: 7

Cevap

7
The correct answer accurately determines the total mission time allowed (66 hours) and subtracts both the travel time for the first leg (22 hours) and the observation halt (22 hours) to find the remaining time. Dividing the remaining distance (1414 miles) by the remaining time (22 hours) gives the required speed.

Adım Adım Çözüm

1
Calculate the total allowed time for the entire route.
24÷4=624 \div 4 = 6 hours
Overall average speed equals total distance divided by total time. Rearranging this gives Total Time = Total Distance / Average Speed.
2
Calculate the time spent completing the first leg.
10÷5=210 \div 5 = 2 hours
Travel time is calculated by dividing the distance traveled by the rate of speed.
3
Determine the remaining time available for the final leg.
6−2−2=26 - 2 - 2 = 2 hours
Convert the 120120-minute halt to 22 hours. Subtract both the first leg's travel time (22 hours) and the observation halt (22 hours) from the total allowed time (66 hours).
4
Calculate the required average speed for the remaining distance.
14÷2=714 \div 2 = 7 mph
The remaining distance (24−10=1424 - 10 = 14 miles) must be completed in the remaining time (22 hours).

Anahtar Kavram

Average Speed for Multi-Segment Trips
Tahmini Süre:2m 0s
ÖncekiSayfa 5 / 6Sonraki
Time, Rate, and Distance Alıştırma Soruları — Armed Services Vocational Aptitude Battery (ASVAB) — Sayfa 5 | Examkin