Add 21/30 and 15/7, Solve 21/30 + 2 1/7 as a fraction

Add 21/30 and 15/7

1^st number: 21/30, 2^nd number: 2 1/7

21/30 + 15/7 is 199/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Likewise, for the 2nd fraction, since 7 × 30 = 210,
15/7 = 15 × 30/7 × 30 = 450/210
Add the two like fractions:
147/210 + 450/210 = 147 + 450/210 = 597/210
597/210 simplified gives 199/70
So, 21/30 + 15/7 = 199/70
In mixed form: 259/70

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