Page 99 - NUMINO Challenge_D1

Type 11-1 Climbing Stairs

Ryan is trying to climb 8 steps on a staircase
by going up 1 or 2 steps at a time. How many
ways are there for Ryan to reach the 8th step?

1 There is 1 way to get to the 1st step. There are 2 ways to get to the 2nd
step, by either going up 1 step two times or going up 2 steps at once.
Find the number of ways to get to the 3rd step.

Number of Steps Ways Number of Ways
1st (1) 1
2nd 2
3rd (1, 1), (2)

2 From which step can you move just once to reach the 4th
step, ?

3 Express the number of ways to reach the 4th step by using the number of
ways you can reach the 2nd and 3rd steps.

4 Find the number of ways to reach the 5th step.
5 Similarly, find the number of ways to reach the 8th step.

96 NUMINO Challenge D1