Solve 9/40+1/8-7/15

$$9 / 40 + 1 / 8 - 7 / 15$$

Evaluate

$$-\frac{7}{60}\approx -0.116666667$$

Solution Steps

Least common multiple of 40 and 8 is 40. Convert \frac{9}{40} and \frac{1}{8} to fractions with denominator 40.

$$\frac{9}{40}+\frac{5}{40}-\frac{7}{15}$$

Since \frac{9}{40} and \frac{5}{40} have the same denominator, add them by adding their numerators.

$$\frac{9+5}{40}-\frac{7}{15}$$

Add 9 and 5 to get 14.

$$\frac{14}{40}-\frac{7}{15}$$

Reduce the fraction \frac{14}{40} to lowest terms by extracting and canceling out 2.

$$\frac{7}{20}-\frac{7}{15}$$

Least common multiple of 20 and 15 is 60. Convert \frac{7}{20} and \frac{7}{15} to fractions with denominator 60.

$$\frac{21}{60}-\frac{28}{60}$$

Since \frac{21}{60} and \frac{28}{60} have the same denominator, subtract them by subtracting their numerators.

$$\frac{21-28}{60}$$

Subtract 28 from 21 to get -7.

$$-\frac{7}{60}$$

Factor

$$-\frac{7}{60} = -0.11666666666666667$$