Add 20/21 and 35/90
20/21 + 35/90 is 169/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
20/21 = 20 × 30/21 × 30 = 600/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
35/90 = 35 × 7/90 × 7 = 245/630 - Add the two like fractions:
600/630 + 245/630 = 600 + 245/630 = 845/630 - 845/630 simplified gives 169/126
- So, 20/21 + 35/90 = 169/126
In mixed form: 143/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+35/90 20/21+70/90 20/42+35/90 60/21+35/90 20/63+35/90