Add 15/27 and 8/21, Solve 15/27 + 8/21 as a fraction

Add 15/27 and 8/21

15/27 + 8/21 is 59/63.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 21 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 27 × 7 = 189,
15/27 = 15 × 7/27 × 7 = 105/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
8/21 = 8 × 9/21 × 9 = 72/189
Add the two like fractions:
105/189 + 72/189 = 105 + 72/189 = 177/189
177/189 simplified gives 59/63
So, 15/27 + 8/21 = 59/63

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