[tex]\begin{gathered} \text{The tax on the first \$8500 is : }\frac{15}{100}\text{ }\times\text{ \$8500} \\ \text{ =0.15 }\times\text{ \$8500} \\ \text{ = \$1275} \\ \text{The Tax on the Reamining income after the first deduction is }\colon\text{ }\frac{18}{100}\text{ }\times\text{ (40,000-8500)} \\ \text{ }\frac{18}{100}\text{ }\times\text{ \$31500} \\ \text{ =\$5670} \\ \text{Total Amount to be paid for income tax is : \$1275 + \$5670 }=\text{ \$6945} \end{gathered}[/tex]