Add 20/36 and 21/90
20/36 + 21/90 is 71/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
20/36 = 20 × 5/36 × 5 = 100/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Add the two like fractions:
100/180 + 42/180 = 100 + 42/180 = 142/180 - 142/180 simplified gives 71/90
- So, 20/36 + 21/90 = 71/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/36+21/90 20/36+42/90 20/72+21/90 60/36+21/90 20/36+63/90