How many different fractions can be made up of the numbers

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How many different fractions can be made up of the numbers 3, 5, 7, 11, 13, 17 so that each fraction contains 2 different numbers? How many of them will be the proper fractions?

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The numbers of fraction which have two different numbers according to @Benjamin wang = 6C2×2!=30. Now you can find the solution of next question. To be proper fraction I can't take the value 2! So, the answer of next question=6C2=15

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Note that all the numbers are mutually coprime integers and therefore there cannot be cancellations in the fractions. Then you only need to count the number of possible pairs.