Subtract 18/9 from 21/36
1st number: 21/36, 2nd number: 2 0/9
21/36 - 18/9 is -17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 36 × 1 = 36,
21/36 = 21 × 1/36 × 1 = 21/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
18/9 = 18 × 4/9 × 4 = 72/36 - Subtract the two like fractions:
21/36 - 72/36 = 21 - 72/36 = -51/36 - After reducing the fraction, the answer is -17/12
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