Subtract 21/5 from 45/12
1st number: 3 9/12, 2nd number: 4 1/5
45/12 - 21/5 is -9/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 5 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
45/12 = 45 × 5/12 × 5 = 225/60 - Likewise, for the 2nd fraction, since 5 × 12 = 60,
21/5 = 21 × 12/5 × 12 = 252/60 - Subtract the two like fractions:
225/60 - 252/60 = 225 - 252/60 = -27/60 - After reducing the fraction, the answer is -9/20
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