how do you do the following? 9/10 - ?= 17/30 and 3/10 + 4/5 = ? first time doing this . Thank you

Answer 1

To add and subtract fractions, they need to have the same denominator.

9/10 - ?= 17/30

- x = 17/30 - 9/10

-x = 17/30 - 27/30

x = 10/30 = 1/3
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3/10 + 4/5 = ?

3/10 + 8/10 = 11/10 = 1 1/10

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