Subtract 18/42 from 7/28
7/28 - 18/42 is -5/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
7/28 = 7 × 3/28 × 3 = 21/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
18/42 = 18 × 2/42 × 2 = 36/84 - Subtract the two like fractions:
21/84 - 36/84 = 21 - 36/84 = -15/84 - After reducing the fraction, the answer is -5/28
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