Solve 21/3--31/4=

$$2 \frac{ 1 }{ 3 } --3 \frac{ 1 }{ 4 } =$$

Evaluate

$$\frac{67}{12}\approx 5.583333333$$

Solution Steps

Multiply 2 and 3 to get 6.

$$\frac{6+1}{3}-\left(-\frac{3\times 4+1}{4}\right)$$

Add 6 and 1 to get 7.

$$\frac{7}{3}-\left(-\frac{3\times 4+1}{4}\right)$$

Multiply 3 and 4 to get 12.

$$\frac{7}{3}-\left(-\frac{12+1}{4}\right)$$

Add 12 and 1 to get 13.

$$\frac{7}{3}-\left(-\frac{13}{4}\right)$$

The opposite of -\frac{13}{4} is \frac{13}{4}.

$$\frac{7}{3}+\frac{13}{4}$$

Least common multiple of 3 and 4 is 12. Convert \frac{7}{3} and \frac{13}{4} to fractions with denominator 12.

$$\frac{28}{12}+\frac{39}{12}$$

Since \frac{28}{12} and \frac{39}{12} have the same denominator, add them by adding their numerators.

$$\frac{28+39}{12}$$

Add 28 and 39 to get 67.

$$\frac{67}{12}$$

Factor

$$\frac{67}{2 ^ {2} \cdot 3} = 5\frac{7}{12} = 5.583333333333333$$