Subtract 4/18 from 81/20
1st number: 4 1/20, 2nd number: 4/18
81/20 - 4/18 is 689/180.
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,
4/18 = 4 × 10/18 × 10 = 40/180 - Subtract the two like fractions:
729/180 - 40/180 = 729 - 40/180 = 689/180 - In mixed form: 3149/180
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