Subtract 70/90 from 45/80
45/80 - 70/90 is -31/144.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
45/80 = 45 × 9/80 × 9 = 405/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
70/90 = 70 × 8/90 × 8 = 560/720 - Subtract the two like fractions:
405/720 - 560/720 = 405 - 560/720 = -155/720 - After reducing the fraction, the answer is -31/144
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Related: 90/80-70/90