Ascientist has two solutions, which she has labeled solution a and solution b. each contains salt. she knows that solution a is 45% salt and solution b is 85% salt. she wants to obtain 160 ounces of a mixture that is 70% salt. how many ounces of each solution should she use?

First off... let's use the decimal format for the percentages, so 85% is 85/100 or 0.85 and 45% is 45/100 or 0.45 and so on

let's say the quantities of each are "a" and "b" respectively

how much salt concentration in A? well, 0.45, so for a quantity "a", that'd be 0.45a

how much satl concentration in B? well 0.85, so for a quantity "b", that'd be 0.85b

now, she wants a mixture of 160ounces with 70% concentration, or 0.7

so the mixture will have a concentration amount of salt of 160 * 0.7



solve for "a", to see how much of the 45% solution will be needed.

what about "b"?  well, b = 160 - a

B. 2 1/2 feet. multiply 2.5 inches by 12 to get thirty inches then divide by 12 to get 2.5 feet