Subtract 20/5 from 21/12
1st number: 1 9/12, 2nd number: 4 0/5
21/12 - 20/5 is -9/4.
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,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 5 × 12 = 60,
20/5 = 20 × 12/5 × 12 = 240/60 - Subtract the two like fractions:
105/60 - 240/60 = 105 - 240/60 = -135/60 - After reducing the fraction, the answer is -9/4
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