Question

If a well was 70-feet deep, the frog climbs 7 feet per hour, and it slips back 2 feet while resting? How long (in hours) will it take for the frog to get out of the well?

Answer 1

13 5/7 hours.

Explanation:

In the first hour it climes a total of 7 - 2 = 5 feet.

After climbing for 13 hours the frog first reaches 13*5 = 65 feet.

From here he has to go another 5 feet . As he travels at 7 feet per hour he takes another 5/7 of hour to reach the top.

Answer 2

14 hours

Explanation:

Given well is 70 ft deep.

Each step of the climb involves moving up at 7 ft/hr and then slips down 2 feet. Assuming the frog rests only once each hour, then the resultant progress made each hour,

= distance climbed - distance lost by slipping

= 7 - 2

= 5 ft / hr

Hence we can say that :

5 feet ---> takes 1 hour

1 foot ---> takes 1/5 hours

70 feet ---> takes (1/5) x 70= 14 hours