Subtract 40/21 from 30/54
1st number: 30/54, 2nd number: 1 19/21
30/54 - 40/21 is -85/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
40/21 = 40 × 18/21 × 18 = 720/378 - Subtract the two like fractions:
210/378 - 720/378 = 210 - 720/378 = -510/378 - After reducing the fraction, the answer is -85/63
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