Subtract 12/3 from 21/42
1st number: 21/42, 2nd number: 4 0/3
21/42 - 12/3 is -7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 3 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 3 × 14 = 42,
12/3 = 12 × 14/3 × 14 = 168/42 - Subtract the two like fractions:
21/42 - 168/42 = 21 - 168/42 = -147/42 - After reducing the fraction, the answer is -7/2
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