Add 81/21 and 20/30
1st number: 3 18/21, 2nd number: 20/30
81/21 + 20/30 is 95/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 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 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Add the two like fractions:
810/210 + 140/210 = 810 + 140/210 = 950/210 - 950/210 simplified gives 95/21
- So, 81/21 + 20/30 = 95/21
In mixed form: 411/21
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