Add 35/70 and 5/21
35/70 + 5/21 is 31/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
35/70 = 35 × 3/70 × 3 = 105/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
5/21 = 5 × 10/21 × 10 = 50/210 - Add the two like fractions:
105/210 + 50/210 = 105 + 50/210 = 155/210 - 155/210 simplified gives 31/42
- So, 35/70 + 5/21 = 31/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 35/70+10/21 35/70+5/42 35/70+15/21 35/70+5/63 35/70+25/21 35/70+35/21