Add 81/70 and 21/30
1st number: 1 11/70, 2nd number: 21/30
81/70 + 21/30 is 13/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 30 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 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Add the two like fractions:
243/210 + 147/210 = 243 + 147/210 = 390/210 - 390/210 simplified gives 13/7
- So, 81/70 + 21/30 = 13/7
In mixed form: 16/7
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