Subtract 18/10 from 42/80
1st number: 42/80, 2nd number: 1 8/10
42/80 - 18/10 is -51/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 10 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Likewise, for the 2nd fraction, since 10 × 8 = 80,
18/10 = 18 × 8/10 × 8 = 144/80 - Subtract the two like fractions:
42/80 - 144/80 = 42 - 144/80 = -102/80 - After reducing the fraction, the answer is -51/40
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