Subtract 42/25 from 18/20
1st number: 18/20, 2nd number: 1 17/25
18/20 - 42/25 is -39/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 25 is 100
Next, find the equivalent fraction of both fractional numbers with denominator 100 - For the 1st fraction, since 20 × 5 = 100,
18/20 = 18 × 5/20 × 5 = 90/100 - Likewise, for the 2nd fraction, since 25 × 4 = 100,
42/25 = 42 × 4/25 × 4 = 168/100 - Subtract the two like fractions:
90/100 - 168/100 = 90 - 168/100 = -78/100 - After reducing the fraction, the answer is -39/50
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