Subtract 42/45 from 12/18
12/18 - 42/45 is -4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
12/18 = 12 × 5/18 × 5 = 60/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
42/45 = 42 × 2/45 × 2 = 84/90 - Subtract the two like fractions:
60/90 - 84/90 = 60 - 84/90 = -24/90 - After reducing the fraction, the answer is -4/15
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