Answer:
10d or less
Step-by-step explanation:
Joanne would want $50 left, and she has $250. 20 - 50 is 200. 20 goes into 100 5 times.
20 goes into 200 10 times. You just add five. (20, 40, 60, 80, 100)
If she wants at least $50 left, she would have to limit how many Dvd's she buys to 10 or less.