Solve =1*10^-3-5*10^-3/20

$$= \frac { 1 \times 10 ^ { - 3 } - 5 \times 10 ^ { - 3 } } { 20 }$$

Evaluate

$$-\frac{1}{5000}=-0.0002$$

Solution Steps

Calculate 10 to the power of -3 and get \frac{1}{1000}.

$$\frac{1\times \frac{1}{1000}-5\times 10^{-3}}{20}$$

Multiply 1 and \frac{1}{1000} to get \frac{1}{1000}.

$$\frac{\frac{1}{1000}-5\times 10^{-3}}{20}$$

Calculate 10 to the power of -3 and get \frac{1}{1000}.

$$\frac{\frac{1}{1000}-5\times \frac{1}{1000}}{20}$$

Multiply 5 and \frac{1}{1000} to get \frac{1}{200}.

$$\frac{\frac{1}{1000}-\frac{1}{200}}{20}$$

Subtract \frac{1}{200} from \frac{1}{1000} to get -\frac{1}{250}.

$$\frac{-\frac{1}{250}}{20}$$

Express \frac{-\frac{1}{250}}{20} as a single fraction.

$$\frac{-1}{250\times 20}$$

Multiply 250 and 20 to get 5000.

$$\frac{-1}{5000}$$

Fraction \frac{-1}{5000} can be rewritten as -\frac{1}{5000} by extracting the negative sign.

$$-\frac{1}{5000}$$

Factor

$$-\frac{1}{5000} = -0.0002$$