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23 votes
23 votes
Wilbur has homework assignments in seven subjects. He only has time to do five of them.

User Koorchik
by
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1 Answer

13 votes
13 votes

Answer:

  • 21 ways

Explanation:

Given

  • Wilbur has 7 subjects' homework
  • He can only do 5 of them

Combination Formula

  • ⁿCₓ = n! / (n - x)! x!

Number of possible ways

  • ⁷C₅ = 7! / 2! x 5!
  • ⇒ 7 x 6 x 5! / 2! x 5!
  • ⇒ 7 x 6 / 2
  • ⇒ 7 x 3
  • 21 ways
User Lundstromski
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3.6k points