Subtract 21/9 from 45/20
1st number: 2 5/20, 2nd number: 2 3/9
45/20 - 21/9 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Likewise, for the 2nd fraction, since 9 × 20 = 180,
21/9 = 21 × 20/9 × 20 = 420/180 - Subtract the two like fractions:
405/180 - 420/180 = 405 - 420/180 = -15/180 - After reducing the fraction, the answer is -1/12
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