Add 81/18 and 40/21
1st number: 4 9/18, 2nd number: 1 19/21
81/18 + 40/21 is 269/42.
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,
40/21 = 40 × 6/21 × 6 = 240/126 - Add the two like fractions:
567/126 + 240/126 = 567 + 240/126 = 807/126 - 807/126 simplified gives 269/42
- So, 81/18 + 40/21 = 269/42
In mixed form: 617/42
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