Subtract 15/8 from 42/80
1st number: 42/80, 2nd number: 1 7/8
42/80 - 15/8 is -27/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 8 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 8 × 10 = 80,
15/8 = 15 × 10/8 × 10 = 150/80 - Subtract the two like fractions:
42/80 - 150/80 = 42 - 150/80 = -108/80 - After reducing the fraction, the answer is -27/20
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