Add 15/21 and 9/10
15/21 + 9/10 is 113/70.
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,
15/21 = 15 × 10/21 × 10 = 150/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Add the two like fractions:
150/210 + 189/210 = 150 + 189/210 = 339/210 - 339/210 simplified gives 113/70
- So, 15/21 + 9/10 = 113/70
In mixed form: 143/70
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