Add 72/21 and 84/72, Solve 3 9/21 + 1 12/72 as a fraction

Add 72/21 and 84/72

1^st number: 3 9/21, 2^nd number: 1 12/72

72/21 + 84/72 is 193/42.

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,
72/21 = 72 × 24/21 × 24 = 1728/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
84/72 = 84 × 7/72 × 7 = 588/504
Add the two like fractions:
1728/504 + 588/504 = 1728 + 588/504 = 2316/504
2316/504 simplified gives 193/42
So, 72/21 + 84/72 = 193/42
In mixed form: 425/42

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