Subtract 42/12 from 18/28
1st number: 18/28, 2nd number: 3 6/12
18/28 - 42/12 is -20/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
42/12 = 42 × 7/12 × 7 = 294/84 - Subtract the two like fractions:
54/84 - 294/84 = 54 - 294/84 = -240/84 - After reducing the fraction, the answer is -20/7
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