Subtract 81/3 from 90/70
1st number: 1 20/70, 2nd number: 27 0/3
90/70 - 81/3 is -180/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 3 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 3 × 70 = 210,
81/3 = 81 × 70/3 × 70 = 5670/210 - Subtract the two like fractions:
270/210 - 5670/210 = 270 - 5670/210 = -5400/210 - After reducing the fraction, the answer is -180/7
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