Solve 9/2-21/4+4

$$\frac{ 9 }{ 2 } - \frac{ 21 }{ 4 } +4$$

Evaluate

$$\frac{13}{4}=3.25$$

Solution Steps

Least common multiple of 2 and 4 is 4. Convert \frac{9}{2} and \frac{21}{4} to fractions with denominator 4.

$$\frac{18}{4}-\frac{21}{4}+4$$

Since \frac{18}{4} and \frac{21}{4} have the same denominator, subtract them by subtracting their numerators.

$$\frac{18-21}{4}+4$$

Subtract 21 from 18 to get -3.

$$-\frac{3}{4}+4$$

Convert 4 to fraction \frac{16}{4}.

$$-\frac{3}{4}+\frac{16}{4}$$

Since -\frac{3}{4} and \frac{16}{4} have the same denominator, add them by adding their numerators.

$$\frac{-3+16}{4}$$

Add -3 and 16 to get 13.

$$\frac{13}{4}$$

Factor

$$\frac{13}{2 ^ {2}} = 3\frac{1}{4} = 3.25$$