Subtract 21/3 from 45/12
1st number: 3 9/12, 2nd number: 7 0/3
45/12 - 21/3 is -13/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 3 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 12 × 1 = 12,
45/12 = 45 × 1/12 × 1 = 45/12 - Likewise, for the 2nd fraction, since 3 × 4 = 12,
21/3 = 21 × 4/3 × 4 = 84/12 - Subtract the two like fractions:
45/12 - 84/12 = 45 - 84/12 = -39/12 - After reducing the fraction, the answer is -13/4
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