Subtract 70/18 from 81/40
1st number: 2 1/40, 2nd number: 3 16/18
81/40 - 70/18 is -671/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
81/40 = 81 × 9/40 × 9 = 729/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
70/18 = 70 × 20/18 × 20 = 1400/360 - Subtract the two like fractions:
729/360 - 1400/360 = 729 - 1400/360 = -671/360
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