Question 1049250

Trying to help my daughter, but it's been a long time since I've done this:

I know to solve for the allowance (X), but the cookie part has stumped me.

Stanley decided to spend his allowance. He bought ice cream for $11.20. He 
spent half of what he had left on a giant cookie, and then bought a piece of fudge for $8.36. He had exactly 4 cents left. How much was his allowance?

Thanks for your help.
<pre>Let amount of allowance be A
After spending 11.20 on ice-cream he had: A - 11.2 left
After spending {{{1/2}}} of remainder on a cookie, he had {{{1/2}}} of remainder, or {{{matrix(1,3, (1/2) * (A - 11.2), or, (A - 11.2)/2)}}} left
After spending $8.36 on the fudge, he had: {{{(A - 11.2)/2 - 8.36}}} left
Since the final amount he was left with was: .04, we can say that:
{{{(A - 11.2)/2 - 8.36 = .04}}}
A - 11.2 - 16.72 = .08 ------ Multiplying by LCD, 2
A - 27.92 = .08
A, or amount of allowance = .08 + 27.92, or {{{highlight_green("$28")}}}