Add 21/27 and 27/28, Solve 21/27 + 27/28 as a fraction

Add 21/27 and 27/28

21/27 + 27/28 is 439/252.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 28 is 756

Next, find the equivalent fraction of both fractional numbers with denominator 756
For the 1st fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756
Likewise, for the 2nd fraction, since 28 × 27 = 756,
27/28 = 27 × 27/28 × 27 = 729/756
Add the two like fractions:
588/756 + 729/756 = 588 + 729/756 = 1317/756
1317/756 simplified gives 439/252
So, 21/27 + 27/28 = 439/252
In mixed form: 1187/252

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