Solve -81+21/4+1/9div(-16)

$$- 81 + 2 \frac { 1 } { 4 } + \frac { 1 } { 9 } \div ( - 16 )$$

Evaluate

$$-\frac{11341}{144}\approx -78.756944444$$

Solution Steps

Multiply 2 and 4 to get 8.

$$-81+\frac{8+1}{4}+\frac{\frac{1}{9}}{-16}$$

Add 8 and 1 to get 9.

$$-81+\frac{9}{4}+\frac{\frac{1}{9}}{-16}$$

Convert -81 to fraction -\frac{324}{4}.

$$-\frac{324}{4}+\frac{9}{4}+\frac{\frac{1}{9}}{-16}$$

Since -\frac{324}{4} and \frac{9}{4} have the same denominator, add them by adding their numerators.

$$\frac{-324+9}{4}+\frac{\frac{1}{9}}{-16}$$

Add -324 and 9 to get -315.

$$-\frac{315}{4}+\frac{\frac{1}{9}}{-16}$$

Express \frac{\frac{1}{9}}{-16} as a single fraction.

$$-\frac{315}{4}+\frac{1}{9\left(-16\right)}$$

Multiply 9 and -16 to get -144.

$$-\frac{315}{4}+\frac{1}{-144}$$

Fraction \frac{1}{-144} can be rewritten as -\frac{1}{144} by extracting the negative sign.

$$-\frac{315}{4}-\frac{1}{144}$$

Least common multiple of 4 and 144 is 144. Convert -\frac{315}{4} and \frac{1}{144} to fractions with denominator 144.

$$-\frac{11340}{144}-\frac{1}{144}$$

Since -\frac{11340}{144} and \frac{1}{144} have the same denominator, subtract them by subtracting their numerators.

$$\frac{-11340-1}{144}$$

Subtract 1 from -11340 to get -11341.

$$-\frac{11341}{144}$$

Factor

$$-\frac{11341}{144} = -78\frac{109}{144} = -78.75694444444444$$