Subtract 72/81 from 90/45
1st number: 2 0/45, 2nd number: 72/81
90/45 - 72/81 is 10/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
90/45 = 90 × 9/45 × 9 = 810/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
72/81 = 72 × 5/81 × 5 = 360/405 - Subtract the two like fractions:
810/405 - 360/405 = 810 - 360/405 = 450/405 - After reducing the fraction, the answer is 10/9
- In mixed form: 11/9
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