Subtract 42/45 from 3/12
3/12 - 42/45 is -41/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
3/12 = 3 × 15/12 × 15 = 45/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Subtract the two like fractions:
45/180 - 168/180 = 45 - 168/180 = -123/180 - After reducing the fraction, the answer is -41/60
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