Solve -2/5+3/4-1/2

$$\frac{ -2 }{ 5 } + \frac{ 3 }{ 4 } - \frac{ 1 }{ 2 }$$

Evaluate

$$-\frac{3}{20}=-0.15$$

Solution Steps

Fraction \frac{-2}{5} can be rewritten as -\frac{2}{5} by extracting the negative sign.

$$-\frac{2}{5}+\frac{3}{4}-\frac{1}{2}$$

Least common multiple of 5 and 4 is 20. Convert -\frac{2}{5} and \frac{3}{4} to fractions with denominator 20.

$$-\frac{8}{20}+\frac{15}{20}-\frac{1}{2}$$

Since -\frac{8}{20} and \frac{15}{20} have the same denominator, add them by adding their numerators.

$$\frac{-8+15}{20}-\frac{1}{2}$$

Add -8 and 15 to get 7.

$$\frac{7}{20}-\frac{1}{2}$$

Least common multiple of 20 and 2 is 20. Convert \frac{7}{20} and \frac{1}{2} to fractions with denominator 20.

$$\frac{7}{20}-\frac{10}{20}$$

Since \frac{7}{20} and \frac{10}{20} have the same denominator, subtract them by subtracting their numerators.

$$\frac{7-10}{20}$$

Subtract 10 from 7 to get -3.

$$-\frac{3}{20}$$

Factor

$$-\frac{3}{20} = -0.15$$