Add 15/21 and 63/28, Solve 15/21 + 2 7/28 as a fraction

Add 15/21 and 63/28

1^st number: 15/21, 2^nd number: 2 7/28

15/21 + 63/28 is 83/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
63/28 = 63 × 3/28 × 3 = 189/84
Add the two like fractions:
60/84 + 189/84 = 60 + 189/84 = 249/84
249/84 simplified gives 83/28
So, 15/21 + 63/28 = 83/28
In mixed form: 227/28

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