Subtract 18/12 from 42/80
1st number: 42/80, 2nd number: 1 6/12
42/80 - 18/12 is -39/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Likewise, for the 2nd fraction, since 12 × 20 = 240,
18/12 = 18 × 20/12 × 20 = 360/240 - Subtract the two like fractions:
126/240 - 360/240 = 126 - 360/240 = -234/240 - After reducing the fraction, the answer is -39/40
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