Add 27/30 and 21/7, Solve 27/30 + 3 0/7 as a fraction

Add 27/30 and 21/7

1^st number: 27/30, 2^nd number: 3 0/7

27/30 + 21/7 is 39/10.

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,
27/30 = 27 × 7/30 × 7 = 189/210
Likewise, for the 2nd fraction, since 7 × 30 = 210,
21/7 = 21 × 30/7 × 30 = 630/210
Add the two like fractions:
189/210 + 630/210 = 189 + 630/210 = 819/210
819/210 simplified gives 39/10
So, 27/30 + 21/7 = 39/10
In mixed form: 39/10

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