Subtract 20/40 from 8/72
8/72 - 20/40 is -7/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
8/72 = 8 × 5/72 × 5 = 40/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Subtract the two like fractions:
40/360 - 180/360 = 40 - 180/360 = -140/360 - After reducing the fraction, the answer is -7/18
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