Add 18/35 and 70/21
1st number: 18/35, 2nd number: 3 7/21
18/35 + 70/21 is 404/105.
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,
70/21 = 70 × 5/21 × 5 = 350/105 - Add the two like fractions:
54/105 + 350/105 = 54 + 350/105 = 404/105 - So, 18/35 + 70/21 = 404/105
In mixed form: 389/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/35+70/21 18/70+70/21 18/35+70/42 54/35+70/21 18/35+70/63 90/35+70/21