Solve -6/10+21/20-3/20-1

$$- \frac{ 6 }{ 10 } + \frac{ 21 }{ 20 } - \frac{ 3 }{ 20 } -1$$

Evaluate

$$-\frac{7}{10}=-0.7$$

Solution Steps

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

$$-\frac{3}{5}+\frac{21}{20}-\frac{3}{20}-1$$

Least common multiple of 5 and 20 is 20. Convert -\frac{3}{5} and \frac{21}{20} to fractions with denominator 20.

$$-\frac{12}{20}+\frac{21}{20}-\frac{3}{20}-1$$

Since -\frac{12}{20} and \frac{21}{20} have the same denominator, add them by adding their numerators.

$$\frac{-12+21}{20}-\frac{3}{20}-1$$

Add -12 and 21 to get 9.

$$\frac{9}{20}-\frac{3}{20}-1$$

Since \frac{9}{20} and \frac{3}{20} have the same denominator, subtract them by subtracting their numerators.

$$\frac{9-3}{20}-1$$

Subtract 3 from 9 to get 6.

$$\frac{6}{20}-1$$

Reduce the fraction \frac{6}{20} to lowest terms by extracting and canceling out 2.

$$\frac{3}{10}-1$$

Convert 1 to fraction \frac{10}{10}.

$$\frac{3}{10}-\frac{10}{10}$$

Since \frac{3}{10} and \frac{10}{10} have the same denominator, subtract them by subtracting their numerators.

$$\frac{3-10}{10}$$

Subtract 10 from 3 to get -7.

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

Factor

$$-\frac{7}{10} = -0.7$$