Add 21/40 and 6/90
21/40 + 6/90 is 71/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
6/90 = 6 × 4/90 × 4 = 24/360 - Add the two like fractions:
189/360 + 24/360 = 189 + 24/360 = 213/360 - 213/360 simplified gives 71/120
- So, 21/40 + 6/90 = 71/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/40+6/90 21/40+12/90 21/80+6/90 63/40+6/90 21/40+18/90 21/40+30/90 21/40+42/90