Subtract 18/12 from 42/45
1st number: 42/45, 2nd number: 1 6/12
42/45 - 18/12 is -17/30.
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,
42/45 = 42 × 4/45 × 4 = 168/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
18/12 = 18 × 15/12 × 15 = 270/180 - Subtract the two like fractions:
168/180 - 270/180 = 168 - 270/180 = -102/180 - After reducing the fraction, the answer is -17/30
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