Subtract 21/20 from 3/12
1st number: 3/12, 2nd number: 1 1/20
3/12 - 21/20 is -4/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
3/12 = 3 × 5/12 × 5 = 15/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Subtract the two like fractions:
15/60 - 63/60 = 15 - 63/60 = -48/60 - After reducing the fraction, the answer is -4/5
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