Subtract 42/80 from 4/8
4/8 - 42/80 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 8 × 10 = 80,
4/8 = 4 × 10/8 × 10 = 40/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Subtract the two like fractions:
40/80 - 42/80 = 40 - 42/80 = -2/80 - After reducing the fraction, the answer is -1/40
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