Add 4/21 and 21/27, Solve 4/21 + 21/27 as a fraction

Add 4/21 and 21/27

4/21 + 21/27 is 61/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
4/21 = 4 × 9/21 × 9 = 36/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189
Add the two like fractions:
36/189 + 147/189 = 36 + 147/189 = 183/189
183/189 simplified gives 61/63
So, 4/21 + 21/27 = 61/63

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