Subtract 90/45 from 70/81
1st number: 70/81, 2nd number: 2 0/45
70/81 - 90/45 is -92/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
70/81 = 70 × 5/81 × 5 = 350/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
90/45 = 90 × 9/45 × 9 = 810/405 - Subtract the two like fractions:
350/405 - 810/405 = 350 - 810/405 = -460/405 - After reducing the fraction, the answer is -92/81
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