Question

check your understanding
practise
for help with #4 and #5, refer to example 1 on pages 145–146.

1. chris purchased the following items:

• 2 binders at $4.99 each
• 1 math set for $3.99
• a backpack for $19.99

find the total cost including 5% gst and 7% pst.

1. ravi purchased 3 dvds for $19.99 each.

find the total cost for the dvds including 5% gst and 6% pst.
for help with #6 and #7, refer to example 2 on page 147.

1. a store discounted items by 50% off the original price one week. the following week an additional 10% was taken off the already reduced price. the regular price of a cd player was $85.00. what is the reduced price in the second week?

Explanation:

Problem 4

Step1: Calculate pre-tax subtotal

$2\times4.99 + 3.99 + 19.99 = 9.98 + 3.99 + 19.99 = 33.96$

Step2: Calculate total tax rate

$5\% + 7\% = 12\% = 0.12$

Step3: Calculate tax amount

$33.96\times0.12 = 4.0752$

Step4: Calculate total cost

$33.96 + 4.0752 = 38.0352$

Step1: Calculate pre-tax subtotal

$3\times19.99 = 59.97$

Step2: Calculate total tax rate

$5\% + 6\% = 11\% = 0.11$

Step3: Calculate tax amount

$59.97\times0.11 = 6.5967$

Step4: Calculate total cost

$59.97 + 6.5967 = 66.5667$

Step1: Define first week discount factor

$1 - 0.50 = 0.50$

Step2: Define second week discount factor

$1 - 0.10 = 0.90$

Step3: Calculate combined discount factor

$0.50\times0.90 = 0.45$

Step4: Calculate final reduced price

$85.00\times0.45 = 38.25$

Answer:

$\$38.04$ (rounded to nearest cent)

---

Problem 5