Hi.
So, you'll notice that we can multiply the denominator by 3 to get 15.
What we do the denominator, we do to the numerator.
5 • 3 = 15
3 • 3 = 9
Now, we have 9/15.
There are 9 counters in 3/5 of a set.
Let me know if you encounter any errors in my answer - I did this in my head.
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