Subtract 90/21 from 1/54
1st number: 1/54, 2nd number: 4 6/21
1/54 - 90/21 is -1613/378.
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,
1/54 = 1 × 7/54 × 7 = 7/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
90/21 = 90 × 18/21 × 18 = 1620/378 - Subtract the two like fractions:
7/378 - 1620/378 = 7 - 1620/378 = -1613/378
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