Subtract 45/90 from 8/40
8/40 - 45/90 is -3/10.
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,
8/40 = 8 × 9/40 × 9 = 72/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
45/90 = 45 × 4/90 × 4 = 180/360 - Subtract the two like fractions:
72/360 - 180/360 = 72 - 180/360 = -108/360 - After reducing the fraction, the answer is -3/10
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