Add 30/21 and 15/28, Solve 1 9/21 + 15/28 as a fraction

Add 30/21 and 15/28

1^st number: 1 9/21, 2^nd number: 15/28

30/21 + 15/28 is 55/28.

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,
30/21 = 30 × 4/21 × 4 = 120/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
15/28 = 15 × 3/28 × 3 = 45/84
Add the two like fractions:
120/84 + 45/84 = 120 + 45/84 = 165/84
165/84 simplified gives 55/28
So, 30/21 + 15/28 = 55/28
In mixed form: 127/28

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