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

Add 15/7 and 21/30

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

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

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

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

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