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VTMO 2017 — Grade 9 — semifinal Question 9

VTMO · VTMO 2017 — Grade 9 — semifinal

Question 9

Ti climbs $8$ stairs, taking $1 , 2$ or $3$ stairs per step. How many ways?
  1. $24$
  2. $34$
  3. $44$
  4. $55$
  5. $81$