Subtract 42/21 from 81/20
1st number: 4 1/20, 2nd number: 2 0/21
81/20 - 42/21 is 41/20.
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,
81/20 = 81 × 21/20 × 21 = 1701/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Subtract the two like fractions:
1701/420 - 840/420 = 1701 - 840/420 = 861/420 - After reducing the fraction, the answer is 41/20
- In mixed form: 21/20
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