Subtract 90/70 from 81/80
1st number: 1 1/80, 2nd number: 1 20/70
81/80 - 90/70 is -153/560.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
81/80 = 81 × 7/80 × 7 = 567/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
90/70 = 90 × 8/70 × 8 = 720/560 - Subtract the two like fractions:
567/560 - 720/560 = 567 - 720/560 = -153/560
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