Question

Alan, Bob and Cindy collected $139.20 during a charity drive event. Bob collected $25.20 more than Alan. Cindy collected $43.80 less than Bob. How much did Bob and Cindy collect altogether?

Answer 1

I got:
Alan `$44.20`
Bob `$69.40`
Cindy `$25.60`
so that Bob and Cindy colected `$95`.

Explanation:

Call the amounts collected by each using their initials `a,b and c`; we get:

`a+b+c=139.20`
`b=a+25.20`
`c=b-43.80`

let us substitute the 2 last equations into the first to get `a`:

`a+a+25.20+a+25.20-43.80=139.20`

so that:

`3a=132.6`

and:

`a=44.2`

that gives us:

`b=44.2+25.2=69.4`

and:

`c=69.4-43.8=25.6`