Subtract 21/54 from 20/21
20/21 - 21/54 is 71/126.
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,
20/21 = 20 × 18/21 × 18 = 360/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Subtract the two like fractions:
360/378 - 147/378 = 360 - 147/378 = 213/378 - After reducing the fraction, the answer is 71/126
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