Add 15/28 and 21/12, Solve 15/28 + 1 9/12 as a fraction

Add 15/28 and 21/12

1^st number: 15/28, 2^nd number: 1 9/12

15/28 + 21/12 is 16/7.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
15/28 = 15 × 3/28 × 3 = 45/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84
Add the two like fractions:
45/84 + 147/84 = 45 + 147/84 = 192/84
192/84 simplified gives 16/7
So, 15/28 + 21/12 = 16/7
In mixed form: 22/7

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