Solve 21/2*(3.25-4)-18.21div(-3)

$$2 \frac { 1 } { 2 } \times ( 3.25 - 4 ) - 18.21 \div ( - 3 )$$

Evaluate

$$4.195$$

Solution Steps

Multiply 2 and 2 to get 4.

$$\frac{4+1}{2}\left(3.25-4\right)-\frac{18.21}{-3}$$

Add 4 and 1 to get 5.

$$\frac{5}{2}\left(3.25-4\right)-\frac{18.21}{-3}$$

Subtract 4 from 3.25 to get -0.75.

$$\frac{5}{2}\left(-0.75\right)-\frac{18.21}{-3}$$

Convert decimal number -0.75 to fraction -\frac{75}{100}. Reduce the fraction -\frac{75}{100} to lowest terms by extracting and canceling out 25.

$$\frac{5}{2}\left(-\frac{3}{4}\right)-\frac{18.21}{-3}$$

Multiply \frac{5}{2} times -\frac{3}{4} by multiplying numerator times numerator and denominator times denominator.

$$\frac{5\left(-3\right)}{2\times 4}-\frac{18.21}{-3}$$

Do the multiplications in the fraction \frac{5\left(-3\right)}{2\times 4}.

$$\frac{-15}{8}-\frac{18.21}{-3}$$

Fraction \frac{-15}{8} can be rewritten as -\frac{15}{8} by extracting the negative sign.

$$-\frac{15}{8}-\frac{18.21}{-3}$$

Expand \frac{18.21}{-3} by multiplying both numerator and the denominator by 100.

$$-\frac{15}{8}-\frac{1821}{-300}$$

Reduce the fraction \frac{1821}{-300} to lowest terms by extracting and canceling out 3.

$$-\frac{15}{8}-\left(-\frac{607}{100}\right)$$

The opposite of -\frac{607}{100} is \frac{607}{100}.

$$-\frac{15}{8}+\frac{607}{100}$$

Least common multiple of 8 and 100 is 200. Convert -\frac{15}{8} and \frac{607}{100} to fractions with denominator 200.

$$-\frac{375}{200}+\frac{1214}{200}$$

Since -\frac{375}{200} and \frac{1214}{200} have the same denominator, add them by adding their numerators.

$$\frac{-375+1214}{200}$$

Add -375 and 1214 to get 839.

$$\frac{839}{200}$$

Factor

$$\frac{839}{2 ^ {3} \cdot 5 ^ {2}} = 4\frac{39}{200} = 4.195$$