Subtract 42/20 from 72/45
1st number: 1 27/45, 2nd number: 2 2/20
72/45 - 42/20 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
72/45 = 72 × 4/45 × 4 = 288/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Subtract the two like fractions:
288/180 - 378/180 = 288 - 378/180 = -90/180 - After reducing the fraction, the answer is -1/2
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