Answer: 5 pieces
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Step-by-step explanation:
Note how
(number of pieces)*(length per piece) = 5*(3/5) = 15/5 = 3
which is the total length of the original rope.
So that's why the answer is 5.
We can get this answer through either guess and check, or we can divide 3 over 3/5 like so
3 divide 3/5 = (3/1) divide by (3/5) = (3/1)*(5/3) = 15/3 = 5
The second fraction 3/5 flips when we divide by it. Also the division changes to a multiplication when we flip the second fraction.