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5 votes
The total cost of a new calculator is

$81.05. This price includes a 10% student

discount. Followed by a 6.5% sales tax.

What was the original price of the

calculator, not including the tax or the

discount?

User David Yell
by
3.9k points

1 Answer

6 votes

This question bus incomplete because it lacks the appropriate options.

Complete Question

The total cost of a new calculator is

$81.05. This price includes a 10% student discount. Followed by a 6.5% sales tax. What was the original price of the calculator, not including the tax or the discount?

A. $77.69

B. $83.99

C. $78.80

D. $84.56

Answer:

D. $84.56

Explanation:

From the question, we are given the following values

Total cost of a new calculator = $81.05

Student discount = 10%

Sales tax = 6.5%

The formula to use is

Total price = Original price ( 1 ± r)

Where r = rate of the discount or sales tax

Step 1

Find the original price of the calculator without the discount

Because we are calculating using discount we are using the minus sign

Total price = $81.05

r = 10% = 0.1

Total price = Original price ( 1 - r)

$81.05 = Original price (1 - 0.1)

$81.05 = Original Price × 0.9

Original price = $81.05÷ 0.9

= $90.055555556

Approximately, the original price without the 10% discount is $90.06

Step 2

Find the Original price without the sales tax

Because we are calculating using sales tax we are using the plus sign

Total price = $90.06

This is because the Original price without the discount = Current total price with sales tax for step 2

r = 6.5% = 0.065

Total price = Original price ( 1 + r)

$90.06 = Original price (1 + 0.065)

$90.06 = Original Price × 1.065

Original price = $90.06÷ 1.065

= $84.563380282

Approximately, the original price without the 10% discount and 6.5% sales tax is $84.56

User Sun Gengze
by
4.0k points