Add 90/21 and 72/56
1st number: 4 6/21, 2nd number: 1 16/56
90/21 + 72/56 is 39/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
72/56 = 72 × 3/56 × 3 = 216/168 - Add the two like fractions:
720/168 + 216/168 = 720 + 216/168 = 936/168 - 936/168 simplified gives 39/7
- So, 90/21 + 72/56 = 39/7
In mixed form: 54/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/42+72/56 90/63+72/56