Exercise 11 Page 156

We want to find the sales tax of a coat. Let's start by calculating the dollar amount of the markup. We can use the percent equation for this. part = percent * whole We are given that the Leather Depot buys a coat from a supplier for $ 90 wholesale and marks up the price by 40 %. Let m represent the dollar amount of the markup. m = 40 % * $ 90 We need to write the percent as a decimal before we can solve the equation that we created. We can do this by ignoring the percent symbol and moving the decimal point two places to the left.

Therefore, 40 % is equal to 0.40, or 0.4. m = 40 % * $ 90 ⇓ m = 0.4 * $ 90 Now we can solve the equation for m. For simplicity, we will ignore the units for now.

We got that m= 36 is a solution to the equation. This means that the dollar amount of the markup is $ 36. Now we can calculate the cost of the coat after the markup. $90 + $ 36 = $ 126 The cost of the coat after the markup is $ 126. We also know that the retail price is $134.82. This price includes the sales tax — in other words, if we add the sales tax to the cost with the markup, we will get the retail price. To find the dollar amount of the sales tax, we need to subtract the cost with the markup from the retail price. $134.82 - $ 126 = $ 8.82 Now we can find the sales tax percent by using the percent equation. We know that the dollar amount of the sales tax is $ 8.82 and the cost with the markup is $ 126. Let n represent the sales tax. part = percent * whole ⇓ 8.82 = n * 126 Let's use the Division Property of Equality to solve our equation for n.

We got that n= 0.07 is a solution to the equation. We can write this decimal as a percent if we move the decimal point two places to the right and ad the percent symbol. 0.07 = 7 % Therefore, the sales tax is 7 %.