Step-by-step explanation:
1. keep the demoninator the same
2. to find the numberator, multiply the demoninator number by the whole number, and add the product of that with the numerator number.
example:
2 3/8 = 19/8
1. so, keep the denominator the same, which means that the denominator is 8
2. to find the numerator, you do:
8 times 2 = 16
16 + 3 = 19
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therefore, the improper fraction of 2 3/8 is 19/8
i hope that helps explain/clarify what you're confused with. :D