Subtract 18/40 from 1/90
1/90 - 18/40 is -79/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
1/90 = 1 × 4/90 × 4 = 4/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Subtract the two like fractions:
4/360 - 162/360 = 4 - 162/360 = -158/360 - After reducing the fraction, the answer is -79/180
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