A farmer has a 10%-solution and a 4%-solution of pesticide. How much of each must she mix to have 336 gal of an 5% solution for her sprayer?
A) 280 gal of 10% solution,
56 gal of 4% solution.
B) 68 gal of 10% solution,
268 gal of 4% solution.
C) 51 gal of 10% solution,
285 gal of 4% solution.
D) 66 gal of 10% solution,
270 gal of 4% solution.
E) 56 gal of 10% solution,
280 gal of 4% solution.

Question

Quizplus · Accepted Answer

Let x be the number of gallons of 10% solution and y be the number of gallons of 4% solution needed. Then we have the system of equations:

x + y = 336 (total solution needed)
0.1x + 0.04y = 0.05(336) (amount of pesticide in final solution)

Solving the system of equations, we get:

x = 56, y = 280

Therefore, the farmer needs 56 gallons of the 10% solution and 280 gallons of the 4% solution. Thus, the best choice is E.

A Farmer Has a 10%-Solution and a 4%-Solution of Pesticide