Subtract 32/40 from 20/72
20/72 - 32/40 is -47/90.
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,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
32/40 = 32 × 9/40 × 9 = 288/360 - Subtract the two like fractions:
100/360 - 288/360 = 100 - 288/360 = -188/360 - After reducing the fraction, the answer is -47/90
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