Subtract 12/20 from 18/72
18/72 - 12/20 is -7/20.
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,
18/72 = 18 × 5/72 × 5 = 90/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
12/20 = 12 × 18/20 × 18 = 216/360 - Subtract the two like fractions:
90/360 - 216/360 = 90 - 216/360 = -126/360 - After reducing the fraction, the answer is -7/20
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