Subtract 90/54 from 18/21
1st number: 18/21, 2nd number: 1 36/54
18/21 - 90/54 is -17/21.
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,
18/21 = 18 × 18/21 × 18 = 324/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
90/54 = 90 × 7/54 × 7 = 630/378 - Subtract the two like fractions:
324/378 - 630/378 = 324 - 630/378 = -306/378 - After reducing the fraction, the answer is -17/21
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