Add 81/21 and 21/70
1st number: 3 18/21, 2nd number: 21/70
81/21 + 21/70 is 291/70.
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,
81/21 = 81 × 10/21 × 10 = 810/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Add the two like fractions:
810/210 + 63/210 = 810 + 63/210 = 873/210 - 873/210 simplified gives 291/70
- So, 81/21 + 21/70 = 291/70
In mixed form: 411/70
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