Add 18/35 and 20/21
18/35 + 20/21 is 22/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
18/35 = 18 × 3/35 × 3 = 54/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Add the two like fractions:
54/105 + 100/105 = 54 + 100/105 = 154/105 - 154/105 simplified gives 22/15
- So, 18/35 + 20/21 = 22/15
In mixed form: 17/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/35+20/21 18/35+40/21 18/70+20/21 18/35+20/42 54/35+20/21 18/35+60/21 18/35+20/63 90/35+20/21