Subtract 81/72 from 7/20
1st number: 7/20, 2nd number: 1 9/72
7/20 - 81/72 is -31/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
7/20 = 7 × 18/20 × 18 = 126/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
81/72 = 81 × 5/72 × 5 = 405/360 - Subtract the two like fractions:
126/360 - 405/360 = 126 - 405/360 = -279/360 - After reducing the fraction, the answer is -31/40
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