Subtract 90/40 from 15/18
1st number: 15/18, 2nd number: 2 10/40
15/18 - 90/40 is -17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
15/18 = 15 × 20/18 × 20 = 300/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
90/40 = 90 × 9/40 × 9 = 810/360 - Subtract the two like fractions:
300/360 - 810/360 = 300 - 810/360 = -510/360 - After reducing the fraction, the answer is -17/12
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