Add 20/21 and 9/10
20/21 + 9/10 is 389/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Add the two like fractions:
200/210 + 189/210 = 200 + 189/210 = 389/210 - So, 20/21 + 9/10 = 389/210
In mixed form: 1179/210
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