A scientist needs 10 liters of a 20% acid solution for an experiment, but she has only a 5% solution and a 40% solution. To the nearest tenth of a liter, about how many liters of the 5% and the 40% solutions should she mix to get the solution she needs? Write and solve an equation to match the situation.

Respuesta :

Answer:

see below

Step-by-step explanation:

Acid in = acid out             acid out = 10 liters of 20% = .2 * 10 = 2

x = 5% amount

10-x = 40% amount

.05x  + .40 ( 10-x) =   .20 (10)

.05x + 4 - .4x = 2

-.35x = -2

x = 5.7 liters   of 5 %        10 - 5.7 = 4.3 liters of 40%