Add 15/21 and 63/42, Solve 15/21 + 1 21/42 as a fraction

Add 15/21 and 63/42

1^st number: 15/21, 2^nd number: 1 21/42

15/21 + 63/42 is 31/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
63/42 = 63 × 1/42 × 1 = 63/42
Add the two like fractions:
30/42 + 63/42 = 30 + 63/42 = 93/42
93/42 simplified gives 31/14
So, 15/21 + 63/42 = 31/14
In mixed form: 23/14

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