Subtract 81/42 from 4/40
1st number: 4/40, 2nd number: 1 39/42
4/40 - 81/42 is -64/35.
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,
4/40 = 4 × 21/40 × 21 = 84/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
81/42 = 81 × 20/42 × 20 = 1620/840 - Subtract the two like fractions:
84/840 - 1620/840 = 84 - 1620/840 = -1536/840 - After reducing the fraction, the answer is -64/35
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