Subtract 9/40 from 18/90
18/90 - 9/40 is -1/40.
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,
18/90 = 18 × 4/90 × 4 = 72/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
9/40 = 9 × 9/40 × 9 = 81/360 - Subtract the two like fractions:
72/360 - 81/360 = 72 - 81/360 = -9/360 - After reducing the fraction, the answer is -1/40
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