The way you posted the problem is ambiguous. Use parenthesis to be clear how you want the dividing order to work.
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If you mean to say 1 over the fraction 2/3, then we would have
1/(2/3) = 1 ÷ 2/3 = 1 * 3/2 = 3/2
Then you can convert to a mixed number getting 1 & 1/2
So if we divide 1 over 2/3, then we end up with the mixed number 1 & 1/2
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Or,
If we have 1/2 over 3, then,
(1/2)/3 = 1/2 ÷ 3 = 1/2 ÷ 3/1 = 1/2 * 1/3 = 1/6
