Subtract 7/90 from 18/40
18/40 - 7/90 is 67/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
7/90 = 7 × 4/90 × 4 = 28/360 - Subtract the two like fractions:
162/360 - 28/360 = 162 - 28/360 = 134/360 - After reducing the fraction, the answer is 67/180
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