Answer:
6 minutes
Explanation:
The ant can crawl 40 cm per minute but is pushed back 5 cm every minute aswell. In total the ant will crawl 35 cm per minute (40 - 5 = 35).
In order to find how long it will take for the ant to reach the hole we divide 210 by 35 (210/35) to get the answer of 6, therefore it takes the ant 6 minutes to reach the hole.