Answer:
72%
Explanation:
1. Add all the 7th graders together, you should get 29.
2. 8 of those 7th graders play drums, so do 29 minus 8 to get the number of 7th graders that don't play drums.
3. now you have the fraction of kids that don't play drums over all kids, 21/29
4. multiply the fraction by 100 (2100/2900)
5. Divide by 29 (72.4137931/100)
6. Round your answer. 72%