Subtract 90/20 from 42/18
1st number: 2 6/18, 2nd number: 4 10/20
42/18 - 90/20 is -13/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
42/18 = 42 × 10/18 × 10 = 420/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
90/20 = 90 × 9/20 × 9 = 810/180 - Subtract the two like fractions:
420/180 - 810/180 = 420 - 810/180 = -390/180 - After reducing the fraction, the answer is -13/6
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