Add 15/45 and 4/21, Solve 15/45 + 4/21 as a fraction

Add 15/45 and 4/21

15/45 + 4/21 is 11/21.

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,
15/45 = 15 × 7/45 × 7 = 105/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
4/21 = 4 × 15/21 × 15 = 60/315
Add the two like fractions:
105/315 + 60/315 = 105 + 60/315 = 165/315
165/315 simplified gives 11/21
So, 15/45 + 4/21 = 11/21

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