Subtract 40/42 from 4/28
4/28 - 40/42 is -17/21.
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,
4/28 = 4 × 3/28 × 3 = 12/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
40/42 = 40 × 2/42 × 2 = 80/84 - Subtract the two like fractions:
12/84 - 80/84 = 12 - 80/84 = -68/84 - After reducing the fraction, the answer is -17/21
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