Subtract 9/8 from 42/80
1st number: 42/80, 2nd number: 1 1/8
42/80 - 9/8 is -3/5.
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,
9/8 = 9 × 10/8 × 10 = 90/80 - Subtract the two like fractions:
42/80 - 90/80 = 42 - 90/80 = -48/80 - After reducing the fraction, the answer is -3/5
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