Jacob’s Idea

To solve 3/4 ÷ 2/5, Jacob writes:

3/4 ÷ 2/5 is the same as 15/20 ÷ 8/20. So the answer to 3/4 ÷ 2/5 is the same as 15 ÷ 8.

  • Which part(s) of Jacob’s claims are correct, if any?
  • Which part(s) of the claims are flawed, if any?
  • Will this method always provide a correct answer?
  • How does this approach relate to the standard invert and multiply algorithm?

(Source: Adapted from Connected Mathematics Program, Michigan State University, 2006)

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