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TIMO - 2017 - Grade 9 - Preliminary Round - Paper 5 Question 22

TIMO · TIMO - 2017 - Grade 9 - Preliminary Round - Paper 5

Question 22

Each day at school, Candace has to climb a flight of stairs with 12 steps. Candace can climb up 1 step or 2 steps only. One day, the 3rd and the 7th step are destroyed and impossible to step on. How many different ways can Candace climb up the stairs?
  1. 12
  2. 20
  3. 233
  4. 40