Subtract 90/20 from 81/12
1st number: 6 9/12, 2nd number: 4 10/20
81/12 - 90/20 is 9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
81/12 = 81 × 5/12 × 5 = 405/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Subtract the two like fractions:
405/60 - 270/60 = 405 - 270/60 = 135/60 - After reducing the fraction, the answer is 9/4
- In mixed form: 21/4
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