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TIMO - 2020 - Grade 9 - Preliminary Round - Paper 2 Question 25

TIMO · TIMO - 2020 - Grade 9 - Preliminary Round - Paper 2

Question 25

A flight of stairs has 10 steps. Each time, Lucy can go up 1 step or 2 steps. The 4th step is destroyed so it cannot be stepped on. How many different ways for Lucy to go up the flight of stairs?
  1. 20
  2. 21
  3. 23
  4. 24