Subtract 42/21 from 21/20
1st number: 1 1/20, 2nd number: 2 0/21
21/20 - 42/21 is -19/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Subtract the two like fractions:
441/420 - 840/420 = 441 - 840/420 = -399/420 - After reducing the fraction, the answer is -19/20
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