Add 21/15 and 27/28, Solve 1 6/15 + 27/28 as a fraction

Add 21/15 and 27/28

1^st number: 1 6/15, 2^nd number: 27/28

21/15 + 27/28 is 331/140.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
27/28 = 27 × 15/28 × 15 = 405/420
Add the two like fractions:
588/420 + 405/420 = 588 + 405/420 = 993/420
993/420 simplified gives 331/140
So, 21/15 + 27/28 = 331/140
In mixed form: 251/140

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