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

Add 12/72 and 12/21

12/72 + 12/21 is 31/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
12/21 = 12 × 24/21 × 24 = 288/504
Add the two like fractions:
84/504 + 288/504 = 84 + 288/504 = 372/504
372/504 simplified gives 31/42
So, 12/72 + 12/21 = 31/42

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