Chapter 2, Problem 7CA

(a)

To determine

To Write: An inequality which describes the given condition.

Answer to Problem 7CA

  $160+12x\le 250$

Explanation of Solution

Given Information:

We have $250 gift card to use at a sporting goods store.

And cost of one pair of sneakers = $ 80,

Cost of one pair of socks = $ 12

Here the cost of one pair of sneakers = $ 80

Then the cost of 2 pairs of sneakers = $\$80\times 2=\$160$

And cost of one pair of socks = $ 12

Then cost of $x$ pair of socks = $ 12 $\times x$ = $ $12x$

Here the value of gift card is fixed which $ 250 is and within this amount we have to buy sneakers and shocks.

  $\Rightarrow$ Total cost of sneakers + Total cost of socks $\le$ 250

  $\Rightarrow 160+12x\le 250$

(b)

To determine

To Describe: the condition represented by $60+80x\le 250$ in this context.

Answer to Problem 7CA

This represent numbers x of pairs sneakers you can buy when you buy 5 pairs of socks.

Explanation of Solution

Given Information:

We have $250 gift card to use at a sporting goods store.

And cost of one pair of sneakers = $ 80,

Cost of one pair of socks = $ 12

In the given inequality, $60+80x\le 250$ , the constant term is 60 and it is a multiple of 12, so it is the cost of 5 socks. And the term 80 $x$ is variable and a multiple of 80, so it is the cost of $x$ sneakers. The term 250 is the fixed value of gift card.

Hence this represents numbers $x$ of pairs sneakers you can buy when you buy 5 pairs of socks.