Add 28/30 and 27/28, Solve 28/30 + 27/28 as a fraction

Add 28/30 and 27/28

28/30 + 27/28 is 797/420.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 30 × 14 = 420,
28/30 = 28 × 14/30 × 14 = 392/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
27/28 = 27 × 15/28 × 15 = 405/420
Add the two like fractions:
392/420 + 405/420 = 392 + 405/420 = 797/420
So, 28/30 + 27/28 = 797/420
In mixed form: 1377/420

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