Add 30/18 and 81/21
1st number: 1 12/18, 2nd number: 3 18/21
30/18 + 81/21 is 116/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
81/21 = 81 × 6/21 × 6 = 486/126 - Add the two like fractions:
210/126 + 486/126 = 210 + 486/126 = 696/126 - 696/126 simplified gives 116/21
- So, 30/18 + 81/21 = 116/21
In mixed form: 511/21
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