Subtract 9/18 from 81/20
1st number: 4 1/20, 2nd number: 9/18
81/20 - 9/18 is 71/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
81/20 = 81 × 9/20 × 9 = 729/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
9/18 = 9 × 10/18 × 10 = 90/180 - Subtract the two like fractions:
729/180 - 90/180 = 729 - 90/180 = 639/180 - After reducing the fraction, the answer is 71/20
- In mixed form: 311/20
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