Subtract 18/90 from 15/12
1st number: 1 3/12, 2nd number: 18/90
15/12 - 18/90 is 21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
15/12 = 15 × 15/12 × 15 = 225/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
18/90 = 18 × 2/90 × 2 = 36/180 - Subtract the two like fractions:
225/180 - 36/180 = 225 - 36/180 = 189/180 - After reducing the fraction, the answer is 21/20
- In mixed form: 11/20
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