Add 3/21 and 81/70
1st number: 3/21, 2nd number: 1 11/70
3/21 + 81/70 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
3/21 = 3 × 10/21 × 10 = 30/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Add the two like fractions:
30/210 + 243/210 = 30 + 243/210 = 273/210 - 273/210 simplified gives 13/10
- So, 3/21 + 81/70 = 13/10
In mixed form: 13/10
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