Solve -9/40-(-8/20

$$- \frac{ 9 }{ 40 } -(- \frac{ 8 }{ 20 }$$

Evaluate

$$\frac{7}{40}=0.175$$

Solution Steps

Reduce the fraction \frac{8}{20} to lowest terms by extracting and canceling out 4.

$$-\frac{9}{40}-\left(-\frac{2}{5}\right)$$

The opposite of -\frac{2}{5} is \frac{2}{5}.

$$-\frac{9}{40}+\frac{2}{5}$$

Least common multiple of 40 and 5 is 40. Convert -\frac{9}{40} and \frac{2}{5} to fractions with denominator 40.

$$-\frac{9}{40}+\frac{16}{40}$$

Since -\frac{9}{40} and \frac{16}{40} have the same denominator, add them by adding their numerators.

$$\frac{-9+16}{40}$$

Add -9 and 16 to get 7.

$$\frac{7}{40}$$

Factor

$$\frac{7}{2 ^ {3} \cdot 5} = 0.175$$