Theo made a donation to a charity. his grandfather agreed to add $4.00 to theo's donation amount and then donate half of that sum. theo's grandfather donated $4.25. write and solve an equation to find the amount of theo's donation

So you have to solve for "donation" - so let's call that X. And the things we know are what the grandfather donated, as a function - meaning based upon - Theo's donation. We'll call that Y.

So Y is equal to 1/2 of $4 plus Theo's donation 0.5*(x+4).

So... 4.25 = 0.5(X+4), solving for X

4.25=0.5x + 2

-2            -2

2.25=0.5x - divide each side by 0.5 to get x alone.

x = 4.50

Plugging back in:

(4.50 + 4.00)*0.5 = 4.25!

d 600 because 15*10*2=300

300+300=600

step-by-step explanation: