Subtract 40/18 from 42/20
1st number: 2 2/20, 2nd number: 2 4/18
42/20 - 40/18 is -11/90.
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,
42/20 = 42 × 9/20 × 9 = 378/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
40/18 = 40 × 10/18 × 10 = 400/180 - Subtract the two like fractions:
378/180 - 400/180 = 378 - 400/180 = -22/180 - After reducing the fraction, the answer is -11/90
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