Add 54/21 and 84/72, Solve 2 12/21 + 1 12/72 as a fraction

Add 54/21 and 84/72

1^st number: 2 12/21, 2^nd number: 1 12/72

54/21 + 84/72 is 157/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
54/21 = 54 × 24/21 × 24 = 1296/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
84/72 = 84 × 7/72 × 7 = 588/504
Add the two like fractions:
1296/504 + 588/504 = 1296 + 588/504 = 1884/504
1884/504 simplified gives 157/42
So, 54/21 + 84/72 = 157/42
In mixed form: 331/42

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