Subtract 70/18 from 90/30
1st number: 3 0/30, 2nd number: 3 16/18
90/30 - 70/18 is -8/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
90/30 = 90 × 3/30 × 3 = 270/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
70/18 = 70 × 5/18 × 5 = 350/90 - Subtract the two like fractions:
270/90 - 350/90 = 270 - 350/90 = -80/90 - After reducing the fraction, the answer is -8/9
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