Add 21/70 and 8/21
21/70 + 8/21 is 143/210.
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,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
8/21 = 8 × 10/21 × 10 = 80/210 - Add the two like fractions:
63/210 + 80/210 = 63 + 80/210 = 143/210 - So, 21/70 + 8/21 = 143/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/70+8/21 21/70+16/21 21/70+8/42 63/70+8/21 21/70+24/21 21/70+8/63 21/70+40/21 21/70+56/21