Add 10/45 and 15/21, Solve 10/45 + 15/21 as a fraction

Add 10/45 and 15/21

10/45 + 15/21 is 59/63.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
10/45 = 10 × 7/45 × 7 = 70/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
15/21 = 15 × 15/21 × 15 = 225/315
Add the two like fractions:
70/315 + 225/315 = 70 + 225/315 = 295/315
295/315 simplified gives 59/63
So, 10/45 + 15/21 = 59/63

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