Add 81/18 and 42/21
1st number: 4 9/18, 2nd number: 2 0/21
81/18 + 42/21 is 13/2.
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,
81/18 = 81 × 7/18 × 7 = 567/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Add the two like fractions:
567/126 + 252/126 = 567 + 252/126 = 819/126 - 819/126 simplified gives 13/2
- So, 81/18 + 42/21 = 13/2
In mixed form: 61/2
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