Subtract 20/80 from 70/90
70/90 - 20/80 is 19/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
70/90 = 70 × 8/90 × 8 = 560/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
20/80 = 20 × 9/80 × 9 = 180/720 - Subtract the two like fractions:
560/720 - 180/720 = 560 - 180/720 = 380/720 - After reducing the fraction, the answer is 19/36
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