Add 81/27 and 21/42
1st number: 3 0/27, 2nd number: 21/42
81/27 + 21/42 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
81/27 = 81 × 14/27 × 14 = 1134/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Add the two like fractions:
1134/378 + 189/378 = 1134 + 189/378 = 1323/378 - 1323/378 simplified gives 7/2
- So, 81/27 + 21/42 = 7/2
In mixed form: 31/2
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