Subtract 81/40 from 7/42
1st number: 7/42, 2nd number: 2 1/40
7/42 - 81/40 is -223/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
7/42 = 7 × 20/42 × 20 = 140/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840 - Subtract the two like fractions:
140/840 - 1701/840 = 140 - 1701/840 = -1561/840 - After reducing the fraction, the answer is -223/120
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