Subtract 40/28 from 30/42
1st number: 30/42, 2nd number: 1 12/28
30/42 - 40/28 is -5/7.
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,
30/42 = 30 × 2/42 × 2 = 60/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Subtract the two like fractions:
60/84 - 120/84 = 60 - 120/84 = -60/84 - After reducing the fraction, the answer is -5/7
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