Subtract 18/20 from 9/72
9/72 - 18/20 is -31/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
9/72 = 9 × 5/72 × 5 = 45/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
18/20 = 18 × 18/20 × 18 = 324/360 - Subtract the two like fractions:
45/360 - 324/360 = 45 - 324/360 = -279/360 - After reducing the fraction, the answer is -31/40
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