Add 81/70 and 15/21
1st number: 1 11/70, 2nd number: 15/21
81/70 + 15/21 is 131/70.
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,
81/70 = 81 × 3/70 × 3 = 243/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210 - Add the two like fractions:
243/210 + 150/210 = 243 + 150/210 = 393/210 - 393/210 simplified gives 131/70
- So, 81/70 + 15/21 = 131/70
In mixed form: 161/70
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