21/4 + 1 1/8 over 4 1/2 expressing your answer as a fraction

Not much of an explaination needed.
(9/4 + 9/8)/9/2=
You could multiply all child fractions with the same number, to remove them.
In this case, 8 would be the best choice to get rid of them. This works as we add the same value both above and under the fraction.

(8*9/4 + 8*9/8)/8*9/2=
(18+9)/36=27/36=3/4

The answer is 3/4 :)

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