Subtract 20/45 from 81/18
1st number: 4 9/18, 2nd number: 20/45
81/18 - 20/45 is 73/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
81/18 = 81 × 5/18 × 5 = 405/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
20/45 = 20 × 2/45 × 2 = 40/90 - Subtract the two like fractions:
405/90 - 40/90 = 405 - 40/90 = 365/90 - After reducing the fraction, the answer is 73/18
- In mixed form: 41/18
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