Subtract 42/5 from 18/4
1st number: 4 2/4, 2nd number: 8 2/5
18/4 - 42/5 is -39/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 5 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
18/4 = 18 × 5/4 × 5 = 90/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
42/5 = 42 × 4/5 × 4 = 168/20 - Subtract the two like fractions:
90/20 - 168/20 = 90 - 168/20 = -78/20 - After reducing the fraction, the answer is -39/10
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