She had $12.65 left from her birthday money.
Step-by-step explanation:
Amount of money Stephanie received:
50 + 15 = $65
Amount of money Stephanie spent :
10.90 + 10.90 + 20.25 + 10.30 = $52.35
(10.90 is written two times, because the question says she spent $10.90 each for TWO CD’s. $10.90 for one CD, and another $10.90 for the second CD.)
Amount of money she had left:
65 - 52.35 = $12.65