Add 5/21 and 84/27, Solve 5/21 + 3 3/27 as a fraction

Add 5/21 and 84/27

1^st number: 5/21, 2^nd number: 3 3/27

5/21 + 84/27 is 211/63.

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,
5/21 = 5 × 9/21 × 9 = 45/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
84/27 = 84 × 7/27 × 7 = 588/189
Add the two like fractions:
45/189 + 588/189 = 45 + 588/189 = 633/189
633/189 simplified gives 211/63
So, 5/21 + 84/27 = 211/63
In mixed form: 322/63

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad