Add 9/10 and 10/21
9/10 + 10/21 is 289/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210 - Add the two like fractions:
189/210 + 100/210 = 189 + 100/210 = 289/210 - So, 9/10 + 10/21 = 289/210
In mixed form: 179/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/10+10/21 9/10+20/21 9/20+10/21 9/10+10/42 27/10+10/21 9/10+30/21 9/30+10/21 9/10+10/63 45/10+10/21 9/10+50/21 9/50+10/21 63/10+10/21 9/10+70/21 9/70+10/21