Subtract 21/30 from 18/9
1st number: 2 0/9, 2nd number: 21/30
18/9 - 21/30 is 13/10.
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,
18/9 = 18 × 10/9 × 10 = 180/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Subtract the two like fractions:
180/90 - 63/90 = 180 - 63/90 = 117/90 - After reducing the fraction, the answer is 13/10
- In mixed form: 13/10
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