Subtract 18/90 from 21/12
1st number: 1 9/12, 2nd number: 18/90
21/12 - 18/90 is 31/20.
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,
21/12 = 21 × 15/12 × 15 = 315/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
18/90 = 18 × 2/90 × 2 = 36/180 - Subtract the two like fractions:
315/180 - 36/180 = 315 - 36/180 = 279/180 - After reducing the fraction, the answer is 31/20
- In mixed form: 111/20
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