Subtract 21/81 from 42/28
1st number: 1 14/28, 2nd number: 21/81
42/28 - 21/81 is 67/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 28 × 81 = 2268,
42/28 = 42 × 81/28 × 81 = 3402/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
21/81 = 21 × 28/81 × 28 = 588/2268 - Subtract the two like fractions:
3402/2268 - 588/2268 = 3402 - 588/2268 = 2814/2268 - After reducing the fraction, the answer is 67/54
- In mixed form: 113/54
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