Add 27/30 and 63/42, Solve 27/30 + 1 21/42 as a fraction

Add 27/30 and 63/42

1^st number: 27/30, 2^nd number: 1 21/42

27/30 + 63/42 is 12/5.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 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 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210
Add the two like fractions:
189/210 + 315/210 = 189 + 315/210 = 504/210
504/210 simplified gives 12/5
So, 27/30 + 63/42 = 12/5
In mixed form: 22/5

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