Add 9/10 and 12/21
9/10 + 12/21 is 103/70.
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,
12/21 = 12 × 10/21 × 10 = 120/210 - Add the two like fractions:
189/210 + 120/210 = 189 + 120/210 = 309/210 - 309/210 simplified gives 103/70
- So, 9/10 + 12/21 = 103/70
In mixed form: 133/70
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