Subtract 45/20 from 72/90
1st number: 72/90, 2nd number: 2 5/20
72/90 - 45/20 is -29/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
72/90 = 72 × 2/90 × 2 = 144/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Subtract the two like fractions:
144/180 - 405/180 = 144 - 405/180 = -261/180 - After reducing the fraction, the answer is -29/20
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