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

Add 15/63 and 63/42

1^st number: 15/63, 2^nd number: 1 21/42

15/63 + 63/42 is 73/42.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 63 × 2 = 126,
15/63 = 15 × 2/63 × 2 = 30/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
63/42 = 63 × 3/42 × 3 = 189/126
Add the two like fractions:
30/126 + 189/126 = 30 + 189/126 = 219/126
219/126 simplified gives 73/42
So, 15/63 + 63/42 = 73/42
In mixed form: 131/42

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