Solve 66.5-4*9/2*7/2/86-4*{left(frac{9{2}right)}^2}

$$\frac{ 66.5-4 \times \frac{ 9 }{ 2 } \times \frac{ 7 }{ 2 } }{ 86-4 \times { \left( \frac{ 9 }{ 2 } \right) }^{ 2 } }$$

Evaluate

$$0.7$$

Solution Steps

Express 4\times \frac{9}{2} as a single fraction.

$$\frac{66.5-\frac{4\times 9}{2}\times \frac{7}{2}}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Multiply 4 and 9 to get 36.

$$\frac{66.5-\frac{36}{2}\times \frac{7}{2}}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Divide 36 by 2 to get 18.

$$\frac{66.5-18\times \frac{7}{2}}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Express 18\times \frac{7}{2} as a single fraction.

$$\frac{66.5-\frac{18\times 7}{2}}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Multiply 18 and 7 to get 126.

$$\frac{66.5-\frac{126}{2}}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Divide 126 by 2 to get 63.

$$\frac{66.5-63}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Subtract 63 from 66.5 to get 3.5.

$$\frac{3.5}{86-4\times \left(\frac{9}{2}\right)^{2}}$$

Calculate \frac{9}{2} to the power of 2 and get \frac{81}{4}.

$$\frac{3.5}{86-4\times \frac{81}{4}}$$

Cancel out 4 and 4.

$$\frac{3.5}{86-81}$$

Subtract 81 from 86 to get 5.

$$\frac{3.5}{5}$$

Expand \frac{3.5}{5} by multiplying both numerator and the denominator by 10.

$$\frac{35}{50}$$

Reduce the fraction \frac{35}{50} to lowest terms by extracting and canceling out 5.

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

Factor

$$\frac{7}{2 \cdot 5} = 0.7$$