Add 81/42 and 5/21, Solve 1 39/42 + 5/21 as a fraction

Add 81/42 and 5/21

1^st number: 1 39/42, 2^nd number: 5/21

81/42 + 5/21 is 13/6.

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,
81/42 = 81 × 1/42 × 1 = 81/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
5/21 = 5 × 2/21 × 2 = 10/42
Add the two like fractions:
81/42 + 10/42 = 81 + 10/42 = 91/42
91/42 simplified gives 13/6
So, 81/42 + 5/21 = 13/6
In mixed form: 21/6

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