Subtract 20/36 from 81/18
1st number: 4 9/18, 2nd number: 20/36
81/18 - 20/36 is 71/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 36 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
81/18 = 81 × 2/18 × 2 = 162/36 - Likewise, for the 2nd fraction, since 36 × 1 = 36,
20/36 = 20 × 1/36 × 1 = 20/36 - Subtract the two like fractions:
162/36 - 20/36 = 162 - 20/36 = 142/36 - After reducing the fraction, the answer is 71/18
- In mixed form: 317/18
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