Add 21/18 and 21/3, Solve 1 3/18 + 7 0/3 as a fraction

Add 21/18 and 21/3

1^st number: 1 3/18, 2^nd number: 7 0/3

21/18 + 21/3 is 49/6.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 3 is 18

Next, find the equivalent fraction of both fractional numbers with denominator 18
For the 1st fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18
Likewise, for the 2nd fraction, since 3 × 6 = 18,
21/3 = 21 × 6/3 × 6 = 126/18
Add the two like fractions:
21/18 + 126/18 = 21 + 126/18 = 147/18
147/18 simplified gives 49/6
So, 21/18 + 21/3 = 49/6
In mixed form: 81/6

MathStep (Works offline)

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