Add 72/21 and 3/42, Solve 3 9/21 + 3/42 as a fraction

Add 72/21 and 3/42

1^st number: 3 9/21, 2^nd number: 3/42

72/21 + 3/42 is 7/2.

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,
72/21 = 72 × 2/21 × 2 = 144/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
3/42 = 3 × 1/42 × 1 = 3/42
Add the two like fractions:
144/42 + 3/42 = 144 + 3/42 = 147/42
147/42 simplified gives 7/2
So, 72/21 + 3/42 = 7/2
In mixed form: 31/2

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