Add 21/42 and 10/7, Solve 21/42 + 1 3/7 as a fraction

Add 21/42 and 10/7

1^st number: 21/42, 2^nd number: 1 3/7

21/42 + 10/7 is 27/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42
Likewise, for the 2nd fraction, since 7 × 6 = 42,
10/7 = 10 × 6/7 × 6 = 60/42
Add the two like fractions:
21/42 + 60/42 = 21 + 60/42 = 81/42
81/42 simplified gives 27/14
So, 21/42 + 10/7 = 27/14
In mixed form: 113/14

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