I would try using a table. It might work better.
4=4 6=5 7=9 8=4 9=2 10=8 11=3 12=9
I do believe the answer is A (sorry if i’m incorrect)
Answer:
The answer is 600 minutes (10 hours)
Step-by-step explanation:
20 minutes = 1 student.
30 students x 20 = 600 minutes
600mins / 60 (because an hour has 60 mins) = 10 hours.
