Subtract 40/28 from 40/42
1st number: 40/42, 2nd number: 1 12/28
40/42 - 40/28 is -10/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
40/42 = 40 × 2/42 × 2 = 80/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Subtract the two like fractions:
80/84 - 120/84 = 80 - 120/84 = -40/84 - After reducing the fraction, the answer is -10/21
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