Subtract 45/72 from 4/20
4/20 - 45/72 is -17/40.
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,
4/20 = 4 × 18/20 × 18 = 72/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
45/72 = 45 × 5/72 × 5 = 225/360 - Subtract the two like fractions:
72/360 - 225/360 = 72 - 225/360 = -153/360 - After reducing the fraction, the answer is -17/40
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