Subtract 20/18 from 42/40
1st number: 1 2/40, 2nd number: 1 2/18
42/40 - 20/18 is -11/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
20/18 = 20 × 20/18 × 20 = 400/360 - Subtract the two like fractions:
378/360 - 400/360 = 378 - 400/360 = -22/360 - After reducing the fraction, the answer is -11/180
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