To subtract fractions with unlike denominators, first find a common denominator of both fractions. In this case, a common denominator would be 4 since both denominators multiplied by a natural number can equal 4. Since 11/4 already has 4 as the denominator, the only fraction that needs to be converted is 9/2. Since multiplying by 1 does not change the value of a number, 9/2 can be multiplied by 2/2 (which is equal to 1). To multiply the fractions, multiply both numerators and both denominators. This results in the fraction 18/4, which is equal to 9/2.
9/2 - 11/4
18/4 - 11/4
Now, since the denominators are the same, just subtract the numerators and keep the denominator.
18/4 - 11/4
(18 - 11) / 4
7/4
The answer is 7/4 or 1 3/4