Subtract 21/4 from 45/12
1st number: 3 9/12, 2nd number: 5 1/4
45/12 - 21/4 is -3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 4 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 4 × 3 = 12,
21/4 = 21 × 3/4 × 3 = 63/12 - Subtract the two like fractions:
45/12 - 63/12 = 45 - 63/12 = -18/12 - After reducing the fraction, the answer is -3/2
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