Subtract 80/90 from 20/40
20/40 - 80/90 is -7/18.
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,
20/40 = 20 × 9/40 × 9 = 180/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
80/90 = 80 × 4/90 × 4 = 320/360 - Subtract the two like fractions:
180/360 - 320/360 = 180 - 320/360 = -140/360 - After reducing the fraction, the answer is -7/18
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