Question

A flight of stairs has 6 steps. david can go up for 1 step, 2 steps or 3 steps each time. how many ways is/are there for david to go up the stairs?

Answer 1

There are 20 ways for David to go up the stairs by 1, 2, or 3 steps each time.

Step-by-step explanation:

To calculate the number of ways David can go up the stairs, we can use the concept of combinations. Since David can go up for 1, 2, or 3 steps each time, there are several possible combinations. Let's list them:

• 1 step + 1 step + 1 step + 1 step + 1 step + 1 step
• 1 step + 1 step + 1 step + 1 step + 2 steps
• 1 step + 1 step + 1 step + 2 steps + 1 step
• 1 step + 1 step + 2 steps + 1 step + 1 step
• 1 step + 2 steps + 1 step + 1 step + 1 step
• 2 steps + 1 step + 1 step + 1 step + 1 step
• 1 step + 1 step + 2 steps + 2 steps
• 1 step + 2 steps + 1 step + 2 steps
• 1 step + 2 steps + 2 steps + 1 step
• 2 steps + 1 step + 1 step + 2 steps
• 2 steps + 1 step + 2 steps + 1 step
• 2 steps + 2 steps + 1 step + 1 step
• 1 step + 3 steps + 3 steps
• 3 steps + 1 step + 3 steps
• 3 steps + 3 steps + 1 step
• 2 steps + 2 steps + 2 steps
• 3 steps + 3 steps
• 2 steps + 3 steps
• 3 steps + 2 steps

So, there are 20 ways for David to go up the stairs.