Add 72/21 and 4/49, Solve 3 9/21 + 4/49 as a fraction

Add 72/21 and 4/49

1^st number: 3 9/21, 2^nd number: 4/49

72/21 + 4/49 is 172/49.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
72/21 = 72 × 7/21 × 7 = 504/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
4/49 = 4 × 3/49 × 3 = 12/147
Add the two like fractions:
504/147 + 12/147 = 504 + 12/147 = 516/147
516/147 simplified gives 172/49
So, 72/21 + 4/49 = 172/49
In mixed form: 325/49

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