Add 72/42 and 2/21, Solve 1 30/42 + 2/21 as a fraction

Add 72/42 and 2/21

1^st number: 1 30/42, 2^nd number: 2/21

72/42 + 2/21 is 38/21.

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,
72/42 = 72 × 1/42 × 1 = 72/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
2/21 = 2 × 2/21 × 2 = 4/42
Add the two like fractions:
72/42 + 4/42 = 72 + 4/42 = 76/42
76/42 simplified gives 38/21
So, 72/42 + 2/21 = 38/21
In mixed form: 117/21

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