Expert: Abe Mantell - 7/23/2008

Question
I'm new to algebra, word problems are difficult for me to understand.
Ex: Sally wishes to mix raisins with granola sell in decorated containers at a  flea market. She can get raisins for $1.69lb and granola for $2.59lb.How many pounds of raisins & granola should she use to make a 6lb mixture worth $2.29? can you please help me understand how to get a equation to anwer this?

Answer
Hello Gail,

Let x=the # of lbs of raisins needed, and
let y=the # of lbs of granola needed.

So...
x+y=6, and
1.69x+2.59y=2.29*6 (i.e. the cost of x lbs of raisins + the cost
of y lbs of granola = the cost of 6 lbs of the mixture)

Thus, we need to solve the two equations:
1. x+y=6, and
2. 1.69x+2.59y=13.74

Solving these gives: x=2 and y=4
==> 2 lbs of raisins & 4 lbs of granola

OK?

Abe