Question

A scientist mixes water containung no salt with a solution that contains 35% salt. she want to obtain 140 ounces of a mixes that is 20% salt. how many ounces and water ounces of the 35% salt solution should she use

Answer 1

w= Volume of water to be mixed

Volume of the 35% salt solution needed: 140-w

Balance equation for salt mass:

0.35(140-w)=0.20 x 140

Solve for w:

49-0.35w= 28

49-28 = 0.35w

21= 0.35w

21/0.35 =w

60 = w

60 ounces of water needed

140-w = 140-60 = 80 ounces of the 35% salt solution