Subtract 18/14 from 7/21
1st number: 7/21, 2nd number: 1 4/14
7/21 - 18/14 is -20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
7/21 = 7 × 2/21 × 2 = 14/42 - Likewise, for the 2nd fraction, since 14 × 3 = 42,
18/14 = 18 × 3/14 × 3 = 54/42 - Subtract the two like fractions:
14/42 - 54/42 = 14 - 54/42 = -40/42 - After reducing the fraction, the answer is -20/21
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