Add 72/21 and 75/6, Solve 3 9/21 + 12 3/6 as a fraction

Add 72/21 and 75/6

1^st number: 3 9/21, 2^nd number: 12 3/6

72/21 + 75/6 is 223/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 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 6 × 7 = 42,
75/6 = 75 × 7/6 × 7 = 525/42
Add the two like fractions:
144/42 + 525/42 = 144 + 525/42 = 669/42
669/42 simplified gives 223/14
So, 72/21 + 75/6 = 223/14
In mixed form: 1513/14

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