Subtract 90/30 from 21/9
1st number: 2 3/9, 2nd number: 3 0/30
21/9 - 90/30 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 9 × 10 = 90,
21/9 = 21 × 10/9 × 10 = 210/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
90/30 = 90 × 3/30 × 3 = 270/90 - Subtract the two like fractions:
210/90 - 270/90 = 210 - 270/90 = -60/90 - After reducing the fraction, the answer is -2/3
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