Q&A - Ask Doubts and Get Answers
Q

A water tank has steps inside it. A monkey is sitting on the topmost step (i.e., the first step). The water level is at the ninth step. (i) He jumps 3 steps down and then jumps back 2 steps up. In how many jumps will he reach the water level?

10.(i)  A water tank has steps inside it. A monkey is sitting on the topmost step (i.e., the first step). The water level is at the ninth step.

 (i) He jumps 3 steps down and then jumps back 2 steps up. In how many jumps will he reach the water level?

Answers (1)
Views

Let the number of steps moved down be represented by positive integers and the number of steps moved up by negative integers.

Given,

Monkey is at the step = 1

Now,

The step after:

1st jump  = 1 + 3 = 4

2nd jump  = 4 + (-2) = 2

3rd jump  = 2 + 3 = 5

4th jump  = 5 + (-2) = 3

5th jump  = 3 + 3 = 6

6th jump = 6 + (-2) = 4

7th jump  = 4 + 3 = 7

8th jump  = 7 + (-2) = 5

9th jump  = 5 + 3 = 8

10th jump = 8 + (-2) = 6

11th jump = 6 + 3 = 9

Therefore, after 11 jumps, the monkey reaches the water level which is at the ninth step.

Exams
Articles
Questions