Add 12/72 and 9/42, Solve 12/72 + 9/42 as a fraction

Add 12/72 and 9/42

12/72 + 9/42 is 8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 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 42 × 12 = 504,
9/42 = 9 × 12/42 × 12 = 108/504
Add the two like fractions:
84/504 + 108/504 = 84 + 108/504 = 192/504
192/504 simplified gives 8/21
So, 12/72 + 9/42 = 8/21

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