Complete question:
Joelwants to buy a new tablet computer from a store having a 20% off sale on all tablet. The tablet he wants has an original cost of $190. He also wants to make sure he has enough money to pay the 5% sales tax.
Answer:
$159.60
Step-by-step explanation:
Given the following :
Sales tax = 5%
Percentage discount = 20%
Original cost = $190
Joel's incorrect expression : 0.95(190)(0.8)
Joel's mistake is the 0.95 which is equivalent to 95% used in Calculating the total cost of the computer. The sales tax increases the total cost of the computer and instead of subtracting 5% sales tax, it should be added.
B.) 20% discount = 0.2 will be deducted from 100%(1)
1 - 0.2 = 0.8
5% sales tax = 0.05 will be added :
1 + 0.05 = 1.05
Original cost = $190
Therefore,
Total cost : Original cost * sales tax * discount
Total cost = $190 * 1.05 * 0.8
Total cost = $159.60
