Question

How much money did she have at first

Answer 1

Step-by-step explanation:

x = the total money she had first.

x - x×1/4 - (x - x×1/4)×1/2 = 15

you see, first we needed to deduct 1/4 of x from x. that left us with (x - x×1/4). and from that we need to deduct 1/2.

now, we can simplify :

(x - x×1/4) = (x×4/4 - x×1/4) = x×3/4

x×3/4 - x×3/4 × 1/2 = 15

x×3/4 - x×3/8 = 15

we multiply both sides by 8 (4 is a factor of 8, so this handled both fractions perfectly) :

x×3×2 - x×3 = 120

6x - 3x = 120

3x = 120

x = $40

she had $40 at the beginning.