Subtract 15/54 from 42/21
1st number: 2 0/21, 2nd number: 15/54
42/21 - 15/54 is 31/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378 - Subtract the two like fractions:
756/378 - 105/378 = 756 - 105/378 = 651/378 - After reducing the fraction, the answer is 31/18
- In mixed form: 113/18
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