Add 21/30 and 98/21, Solve 21/30 + 4 14/21 as a fraction

Add 21/30 and 98/21

1^st number: 21/30, 2^nd number: 4 14/21

21/30 + 98/21 is 161/30.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
98/21 = 98 × 10/21 × 10 = 980/210
Add the two like fractions:
147/210 + 980/210 = 147 + 980/210 = 1127/210
1127/210 simplified gives 161/30
So, 21/30 + 98/21 = 161/30
In mixed form: 511/30

MathStep (Works offline)

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