Add 4/20 and 21/90
4/20 + 21/90 is 13/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
4/20 = 4 × 9/20 × 9 = 36/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Add the two like fractions:
36/180 + 42/180 = 36 + 42/180 = 78/180 - 78/180 simplified gives 13/30
- So, 4/20 + 21/90 = 13/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/20+21/90 4/20+42/90 4/40+21/90 12/20+21/90 4/20+63/90 4/60+21/90 28/20+21/90