Question

Difficulty: HardBasic Ratios

Match each military and logistics operational scenario to the correct final mathematical ratio. Read the conditions carefully, as some require calculating a new ratio after a change occurs.

  • A naval strike group contains cruisers, destroyers, and frigates. For every 22 cruisers, there are 55 destroyers. The number of frigates equals the combined number of cruisers and destroyers. Find the ratio of destroyers to the total number of ships.5:145:14
  • A unit has 6060 personnel total, with an initial officer to enlisted ratio of 3:73:7. After 66 officers are transferred out (while enlisted numbers remain unchanged), find the new ratio of officers to enlisted personnel.2:72:7
  • A fuel mixture correctly requires 33 parts additive per 88 parts base fuel. A technician mistakenly uses 44 parts additive per 1010 parts base fuel instead. If both scenarios use exactly 4040 gallons of base fuel, find the ratio of the correct additive amount to the mistakenly used additive amount.15:1615:16
  • A supply convoy's ratio of cargo trucks to escort vehicles is 5:25:2. The convoy has 3535 total vehicles. If 11 escort vehicle breaks down and leaves the convoy, find the new ratio of escort vehicles to cargo trucks.9:259:25

Answer

The correct matches are: Scenario 1 maps to 5:14, Scenario 2 maps to 2:7, Scenario 3 maps to 15:16, and Scenario 4 maps to 9:25.
Each scenario involves distinct ratio logic: Scenario 1 requires combining parts to find a whole. Scenarios 2 and 4 require breaking a total into parts using an initial ratio, subtracting from one part, and writing a new simplified ratio. Scenario 3 requires using part-to-part logic to find an unknown part given a specific base, then comparing the two results.

Step-by-Step Solution

1
Calculate the ratios for the Naval Strike Group (Scenario 1).
The total proportion is 22 (cruisers) + 55 (destroyers) + 77 (frigates) = 1414. The ratio of destroyers to total ships is 5:145:14.
You must establish the total baseline by summing the parts before finding the part-to-whole ratio.
2
Determine the new personnel ratio (Scenario 2).
Initially, officers = 1818 and enlisted = 4242. Subtracting 66 officers leaves 1212. The new ratio is 12:4212:42, simplified to 2:72:7.
Changes to one subset of a population require determining the original absolute values first.
3
Compare the fuel additive amounts (Scenario 3).
Correct additive is 38×40=15\frac{3}{8} \times 40 = 15. Mistaken additive is 410×40=16\frac{4}{10} \times 40 = 16. The ratio is 15:1615:16.
Scaling both ratios up to the common base fuel amount of 4040 reveals the exact additive quantities to compare.
4
Adjust the convoy vehicles ratio (Scenario 4).
Initially, cargo = 2525 and escort = 1010. Subtracting 11 escort leaves 99. The required ratio of escort to cargo is 9:259:25.
Calculating initial absolute quantities is necessary before applying the subtraction of 11 vehicle and interpreting the final specific order requested.

Key Concept

Applying part-to-part and part-to-whole ratio relationships to calculate absolute values, applying condition changes, and then re-evaluating and simplifying the final ratios.

Alternative Method

For Scenario 2, you can also calculate the fractional drop without finding absolute enlisted numbers. The officer count drops from 1818 to 1212, which is exactly 23\frac{2}{3} of the original amount. Thus, the new ratio must simply be 23\frac{2}{3} of the original officer portion (33) against the same enlisted portion (77), resulting directly in a 2:72:7 ratio.
Estimated Time:2m 30s
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