Question

Five years ago, a typical 70” TV cost about $2400. Now a similar TV costs approximately $1680. What is the percent decrease in TV price?

Answer 1

The percent decrease in the TV price is 30%.

The percent decrease in the price of the TV can be calculated using the formula:

Percent Decrease=
`(Original Price - New Price)/(Original Price) *100`

Substituting the given values:

Percent Decrease=(
`(2400−1680)/(2400)` )×100=(
`(720)/(2400)` )×100=0.3×100=30%

Therefore, the percent decrease in the TV price is 30%.

This means that the price has decreased by 30% over the five-year period. The calculation is based on the difference between the original price five years ago ($2400) and the current price ($1680), relative to the original price.

Answer 2

The percentage decrease in TV price after five years is 6.89

Explanation:

Given as :

The cost of TV five years ago = $ 2400

The present cost of TV = $ 1680

Let The decrease percentage in five years = x

So, The cost of TV after T year = Present cost ×
`(1-(Rate)/(100))^(Time)`

Or, $ 1680 = $ 2400 ×
`(1-(Rate)/(100))^(5)`

Or, 0.7 =
`(1-(Rate)/(100))^(5)`

Or,
`(0.7)^{(1)/(5)}` = 1 -
`(x)/(100)`

Or, 0.9311 = 1 -
`(x)/(100)`

Or,
`(x)/(100)` = 1 - 0.9311

∴,
`(x)/(100)` = 0.0689

I.e x = 0.0689 × 100 = 6.89

Hence The percentage decrease in TV price after five years is 6.89 Answer