Add 21/42 and 84/72, Solve 21/42 + 1 12/72 as a fraction

Add 21/42 and 84/72

1^st number: 21/42, 2^nd number: 1 12/72

21/42 + 84/72 is 5/3.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
84/72 = 84 × 7/72 × 7 = 588/504
Add the two like fractions:
252/504 + 588/504 = 252 + 588/504 = 840/504
840/504 simplified gives 5/3
So, 21/42 + 84/72 = 5/3
In mixed form: 12/3

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