Subtract 45/20 from 21/18
1st number: 1 3/18, 2nd number: 2 5/20
21/18 - 45/20 is -13/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Subtract the two like fractions:
210/180 - 405/180 = 210 - 405/180 = -195/180 - After reducing the fraction, the answer is -13/12
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