Subtract 42/20 from 12/9
1st number: 1 3/9, 2nd number: 2 2/20
12/9 - 42/20 is -23/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
12/9 = 12 × 20/9 × 20 = 240/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Subtract the two like fractions:
240/180 - 378/180 = 240 - 378/180 = -138/180 - After reducing the fraction, the answer is -23/30
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