Subtract 90/80 from 18/70
1st number: 18/70, 2nd number: 1 10/80
18/70 - 90/80 is -243/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
18/70 = 18 × 8/70 × 8 = 144/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
90/80 = 90 × 7/80 × 7 = 630/560 - Subtract the two like fractions:
144/560 - 630/560 = 144 - 630/560 = -486/560 - After reducing the fraction, the answer is -243/280
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