Add 63/21 and 81/42, Solve 3 0/21 + 1 39/42 as a fraction

Add 63/21 and 81/42

1^st number: 3 0/21, 2^nd number: 1 39/42

63/21 + 81/42 is 69/14.

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,
63/21 = 63 × 2/21 × 2 = 126/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42
Add the two like fractions:
126/42 + 81/42 = 126 + 81/42 = 207/42
207/42 simplified gives 69/14
So, 63/21 + 81/42 = 69/14
In mixed form: 413/14

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