Subtract 1/42 from 81/40
1st number: 2 1/40, 2nd number: 1/42
81/40 - 1/42 is 1681/840.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
1/42 = 1 × 20/42 × 20 = 20/840 - Subtract the two like fractions:
1701/840 - 20/840 = 1701 - 20/840 = 1681/840 - In mixed form: 21/840
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