Subtract 90/80 from 70/81
1st number: 70/81, 2nd number: 1 10/80
70/81 - 90/80 is -169/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 80 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 81 × 80 = 6480,
70/81 = 70 × 80/81 × 80 = 5600/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
90/80 = 90 × 81/80 × 81 = 7290/6480 - Subtract the two like fractions:
5600/6480 - 7290/6480 = 5600 - 7290/6480 = -1690/6480 - After reducing the fraction, the answer is -169/648
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