Subtract 25/21 from 18/54
1st number: 18/54, 2nd number: 1 4/21
18/54 - 25/21 is -6/7.
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,
18/54 = 18 × 7/54 × 7 = 126/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
25/21 = 25 × 18/21 × 18 = 450/378 - Subtract the two like fractions:
126/378 - 450/378 = 126 - 450/378 = -324/378 - After reducing the fraction, the answer is -6/7
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