Add 21/72 and 30/40
21/72 + 30/40 is 25/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
30/40 = 30 × 9/40 × 9 = 270/360 - Add the two like fractions:
105/360 + 270/360 = 105 + 270/360 = 375/360 - 375/360 simplified gives 25/24
- So, 21/72 + 30/40 = 25/24
In mixed form: 11/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/72+30/40 21/72+60/40 21/72+30/80 63/72+30/40 21/72+90/40