Add 21/15 and 84/28, Solve 1 6/15 + 3 0/28 as a fraction

Add 21/15 and 84/28

1^st number: 1 6/15, 2^nd number: 3 0/28

21/15 + 84/28 is 22/5.

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,
84/28 = 84 × 15/28 × 15 = 1260/420
Add the two like fractions:
588/420 + 1260/420 = 588 + 1260/420 = 1848/420
1848/420 simplified gives 22/5
So, 21/15 + 84/28 = 22/5
In mixed form: 42/5

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