Subtract 42/12 from 20/45
1st number: 20/45, 2nd number: 3 6/12
20/45 - 42/12 is -55/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
20/45 = 20 × 4/45 × 4 = 80/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
42/12 = 42 × 15/12 × 15 = 630/180 - Subtract the two like fractions:
80/180 - 630/180 = 80 - 630/180 = -550/180 - After reducing the fraction, the answer is -55/18
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