Subtract 72/18 from 45/20
1st number: 2 5/20, 2nd number: 4 0/18
45/20 - 72/18 is -7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
72/18 = 72 × 10/18 × 10 = 720/180 - Subtract the two like fractions:
405/180 - 720/180 = 405 - 720/180 = -315/180 - After reducing the fraction, the answer is -7/4
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