Soru

Zorluk: ZorRatio and Proportion Word Problems

A chemical storage vessel contains three industrial solvents—Solvent A, Solvent B, and Solvent C—blended in the initial ratio of 2:5:72 : 5 : 7, respectively. After 2424 liters of Solvent A and 1212 liters of Solvent B are added to the vessel, the ratio of Solvent A to Solvent B becomes 4:74 : 7. What was the initial volume, in liters, of Solvent C in the vessel?

Cevap: 140 liters

Cevap

The initial volume of Solvent C in the vessel was 140 liters.
Defining the initial amounts of Solvents A, B, and C as 2x2x, 5x5x, and 7x7x, respectively, the addition of 2424 liters of Solvent A and 1212 liters of Solvent B yields the ratio equation 2x+245x+12=47\frac{2x + 24}{5x + 12} = \frac{4}{7}. Cross-multiplying gives 14x+168=20x+4814x + 168 = 20x + 48, which simplifies to 6x=1206x = 120 and x=20x = 20. The initial volume of Solvent C is therefore 7×20=1407 \times 20 = 140 liters.

Adım Adım Çözüm

1
Express the initial quantities of the three solvents in terms of a common ratio multiplier xx.
Solvent A = 2x2x, Solvent B = 5x5x, Solvent C = 7x7x.
A ratio of 2:5:72 : 5 : 7 implies the actual quantities are proportional to 2, 5, and 7 by a factor xx.
2
Set up an equation representing the modified ratio of Solvent A to Solvent B.
2x+245x+12=47\frac{2x + 24}{5x + 12} = \frac{4}{7}
Adding 24 liters to Solvent A yields 2x+242x + 24 liters, and adding 12 liters to Solvent B yields 5x+125x + 12 liters.
3
Solve the algebraic equation for xx.
7(2x+24)=4(5x+12)    14x+168=20x+48    6x=120    x=207(2x + 24) = 4(5x + 12) \implies 14x + 168 = 20x + 48 \implies 6x = 120 \implies x = 20.
Cross-multiplication converts the ratio comparison into a linear equation.
4
Compute the initial volume of Solvent C.
Initial volume of Solvent C = 7x=7(20)=1407x = 7(20) = 140 liters.
Substitute x=20x = 20 into the expression 7x7x for the original amount of Solvent C.

Anahtar Kavram

Ratio scaling and algebraic modeling of partial additions
Bu soruyu puanla