Subtract 70/40 from 42/80
1st number: 42/80, 2nd number: 1 30/40
42/80 - 70/40 is -49/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 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 40 × 2 = 80,
70/40 = 70 × 2/40 × 2 = 140/80 - Subtract the two like fractions:
42/80 - 140/80 = 42 - 140/80 = -98/80 - After reducing the fraction, the answer is -49/40
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