There is well of depth 30 m and frog is at bottom of the well. He jumps 3 m in…

2024

There is well of depth 30 m and frog is at bottom of the well. He jumps 3 m in one day and falls back 2 m in the same day. How many days will it take for the frog to come out of the well?

  1. A.

    28 days

  2. B.

    31 days

  3. C.

    20 days

  4. D.

    26 days

Attempted by 34 students.

Show answer & explanation

Correct answer: A

Answer: 28 days

Explanation:

  • Each full day the frog gains a net of 1 m: it jumps 3 m during the day and slips 2 m at night (3 - 2 = 1).

  • After 27 full days the frog has gained 27 m and is at a height of 27 m.

  • On the 28th day the frog jumps 3 m from 27 m to reach 30 m and escapes the well before slipping back.

Therefore, the frog comes out of the well on the 28th day.

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