Solve -2/5+1/10+9/10-1/5

$$- \frac { 2 } { 5 } + \frac { 1 } { 10 } + \frac { 9 } { 10 } - \frac { 1 } { 5 }$$

Evaluate

$$\frac{2}{5}=0.4$$

Solution Steps

Least common multiple of 5 and 10 is 10. Convert -\frac{2}{5} and \frac{1}{10} to fractions with denominator 10.

$$-\frac{4}{10}+\frac{1}{10}+\frac{9}{10}-\frac{1}{5}$$

Since -\frac{4}{10} and \frac{1}{10} have the same denominator, add them by adding their numerators.

$$\frac{-4+1}{10}+\frac{9}{10}-\frac{1}{5}$$

Add -4 and 1 to get -3.

$$-\frac{3}{10}+\frac{9}{10}-\frac{1}{5}$$

Since -\frac{3}{10} and \frac{9}{10} have the same denominator, add them by adding their numerators.

$$\frac{-3+9}{10}-\frac{1}{5}$$

Add -3 and 9 to get 6.

$$\frac{6}{10}-\frac{1}{5}$$

Reduce the fraction \frac{6}{10} to lowest terms by extracting and canceling out 2.

$$\frac{3}{5}-\frac{1}{5}$$

Since \frac{3}{5} and \frac{1}{5} have the same denominator, subtract them by subtracting their numerators.

$$\frac{3-1}{5}$$

Subtract 1 from 3 to get 2.

$$\frac{2}{5}$$

Factor

$$\frac{2}{5} = 0.4$$