Subtract 40/6 from 18/21
1st number: 18/21, 2nd number: 6 4/6
18/21 - 40/6 is -122/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
40/6 = 40 × 7/6 × 7 = 280/42 - Subtract the two like fractions:
36/42 - 280/42 = 36 - 280/42 = -244/42 - After reducing the fraction, the answer is -122/21
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