Add 7/42 and 63/21, Solve 7/42 + 3 0/21 as a fraction

Add 7/42 and 63/21

1^st number: 7/42, 2^nd number: 3 0/21

7/42 + 63/21 is 19/6.

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

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
7/42 = 7 × 1/42 × 1 = 7/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
63/21 = 63 × 2/21 × 2 = 126/42
Add the two like fractions:
7/42 + 126/42 = 7 + 126/42 = 133/42
133/42 simplified gives 19/6
So, 7/42 + 63/21 = 19/6
In mixed form: 31/6

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