Add 21/30 and 27/7, Solve 21/30 + 3 6/7 as a fraction

Add 21/30 and 27/7

1^st number: 21/30, 2^nd number: 3 6/7

21/30 + 27/7 is 319/70.

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,
27/7 = 27 × 30/7 × 30 = 810/210
Add the two like fractions:
147/210 + 810/210 = 147 + 810/210 = 957/210
957/210 simplified gives 319/70
So, 21/30 + 27/7 = 319/70
In mixed form: 439/70

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