Add 21/63 and 35/72, Solve 21/63 + 35/72 as a fraction

Add 21/63 and 35/72

21/63 + 35/72 is 59/72.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
35/72 = 35 × 7/72 × 7 = 245/504
Add the two like fractions:
168/504 + 245/504 = 168 + 245/504 = 413/504
413/504 simplified gives 59/72
So, 21/63 + 35/72 = 59/72

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