Answer:No
Explanation:
10 bags of balloons
= 10 minutes for each so
10*10 is 100 minutes which is equal to an hour and 40 minutes.
If jack starts at 1:20 and 1 hour and 40 minutes passes by, it would be 3 o clock already. His friends aka brothers get out of school at 2:30 but it takes them 20 minutes to get back so it would 2:50 when they get back. Jack finishes all the balloons at 3 o clock which means he will not finish before they get out of school.