Solve -3/12+4/9-7/18

$$- \frac { 3 } { 12 } + \frac { 4 } { 9 } - \frac { 7 } { 18 }$$

Evaluate

$$-\frac{7}{36}\approx -0.194444444$$

Solution Steps

Reduce the fraction \frac{3}{12} to lowest terms by extracting and canceling out 3.

$$-\frac{1}{4}+\frac{4}{9}-\frac{7}{18}$$

Least common multiple of 4 and 9 is 36. Convert -\frac{1}{4} and \frac{4}{9} to fractions with denominator 36.

$$-\frac{9}{36}+\frac{16}{36}-\frac{7}{18}$$

Since -\frac{9}{36} and \frac{16}{36} have the same denominator, add them by adding their numerators.

$$\frac{-9+16}{36}-\frac{7}{18}$$

Add -9 and 16 to get 7.

$$\frac{7}{36}-\frac{7}{18}$$

Least common multiple of 36 and 18 is 36. Convert \frac{7}{36} and \frac{7}{18} to fractions with denominator 36.

$$\frac{7}{36}-\frac{14}{36}$$

Since \frac{7}{36} and \frac{14}{36} have the same denominator, subtract them by subtracting their numerators.

$$\frac{7-14}{36}$$

Subtract 14 from 7 to get -7.

$$-\frac{7}{36}$$

Factor

$$-\frac{7}{36} = -0.19444444444444445$$