Answer: $18.34
Step-by-step explanation: the first step is to find out how much money she had before she bought the hair clip so you would need to add $7.99 and $29.33 and I got $37.32, after that you need to subtract your starting amount of money ($18.98) from $37.32 and I got 18.34 so you received $18.98 from your grandma.