61.2k views
4 votes
Melanie buys a carrying case for her new laptop, which costs 125% as much as her old laptop case. The price of her new laptop carrying case is $65. If n represents the cost of her old laptop carrying case, which proportion can be used to find n?

Melanie buys a carrying case for her new laptop, which costs 125% as much as her old-example-1

2 Answers

4 votes

Final answer:

To find the cost of Melanie's old laptop case (n), we set up the proportion 1.25n / n = $65 / n and solve for n, which involves dividing $65 by 1.25 to find the original price.

Step-by-step explanation:

The question is asking for a proportion that can be used to find the cost n of Melanie's old laptop carrying case given that her new laptop carrying case costs 125% as much as the old one and is priced at $65. To find the proportion, we set up a ratio equal to 125% (or 1.25 as a decimal), with the first ratio being the cost of the new case (n times 1.25) to n, and the second ratio being the known price of the new case ($65) to the unknown price of the old case (n).

The correct proportion is thus:

1.25n / n = $65 / n

To solve for n, we can then set up the equation 1.25n = $65 and divide both sides by 1.25 to isolate n, which gives:

n = $65 / 1.25

We can then calculate n to find the cost of Melanie's old laptop carrying case.

User Mdebeus
by
5.2k points
5 votes

Answer:

C

Step-by-step explanation:

Because don't know old laptop cost.

So 65 dollars represent 100% and n(old case) represents 125%.

User Tvkanters
by
5.2k points