Question

In a dye company, dark blue dye solution has a 27% concentration. Another lighter shade dye solution has an 11% concentration. How many liters’ of the second solution must be added to the 10L of the first solution to make a solution of 13% concentrated?

1. 68 L
2. 70 L
3. 72 L
4. 78 L
5. 75 L

Answer 1

Correct Answer - Option 2 : 70 L

Given:

Concentration of first solution = 27%

Concentration of second Solution = 11%

Concentration of final solution = 13%

Calculation:

Let required amount of second solution to be added = ‘a’ L

∴ (27 × 10 + 11a)/(10 + a) = 13

⇒ 270 + 11a = 130 + 13a

⇒ 2a = 140

⇒ a = 70

∴ 70L of second solution must be added.