Add 21/40 and 18/5
1st number: 21/40, 2nd number: 3 3/5
21/40 + 18/5 is 33/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 5 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 5 × 8 = 40,
18/5 = 18 × 8/5 × 8 = 144/40 - Add the two like fractions:
21/40 + 144/40 = 21 + 144/40 = 165/40 - 165/40 simplified gives 33/8
- So, 21/40 + 18/5 = 33/8
In mixed form: 41/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/40+18/5 21/40+36/5 21/80+18/5 21/40+18/10 63/40+18/5 21/40+54/5 21/40+18/15 21/40+90/5 21/40+18/25 21/40+18/35