math problem help!!!!

Test Preparation SAT Preparation
1

<p>During a sale, a customer can buy one shirt for x dollars. Each additional shirt the customer buys costs z dollars less than the first shirt. For example. the cost of the second shirt is x-z dollars. Which of the following represents the customer's cost, in dollars, for n shirts bought during this sale?</p>

<p>a) x + (n - 1)(x - z)
b) x + n(x - z)
c) n(x - z)
d) [x + (x - z) ] / n
e) (x - z) + [(x - z) / n]</p>

<p>Completely and utterly confused... the answer is A, can anyone help and explain how to solve this? T___T</p>

2

<p>Oh, totally kidding, sorry, I just realized I completely read the problem wrong… um, I don’t know how to delete a thread…</p>

3

<p>If somebody is interested here is the solution:</p>

<p>n - total number of t-shirts
one of them costs 1*x, so (n-1)(x-z) is cost of the other shirts.</p>

<p>Total cost of shirts is
1*x+(n-1)(x-z)</p>

4

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<p>Can you explain to me the n-1, I don’t get its point?</p>

5

<p>You want to buy a total of n shirts. After you pay full price for the first shirt, you now have one fewer shirt left to buy at the reduced price: n-1 shirts…each at a cost of (x-z) dollars.</p>

<p>If you are not seeing this one algebraically, make up numbers for the variables and it will probably all make more sense.</p>