Sat math question

Test Preparation SAT Preparation
1

<p>Suppose these are the 5 cards:</p>

<ul>
<li> @ # $ % </li>
</ul>

<p>If the 5 cards shown above are placed in a row so the # is never at either end, how many different arrangements are possible?</p>

<p>The correct answer is 72 but how would you get that?</p>

<p>The college board said 5!= 120, since there is one card limited, 4!=24, you would do 120-24-24 in order to get the number of different combination. </p>

<p>My method: I tried the following way</p>

<p>___ x ___ x ___ x ___ x ___</p>

<p>1 x 3 x 2 x 1 x 1 ( i put 1 in the first and last blank in order to limit them and i put how many cards could fit the other blanks)</p>

<p>PLEASE EXPLAIN TO ME How to do this using my method or another method? Thank You</p>

2

<p>OK so you 4 choices for the first slot because a # cant be there. And you have 3 choices for the last slot because, 1 choice has been used and a # cant be there either. You have 3, 2 and 1 choices for the middle slots</p>

<p>4x3x2x1x3=72</p>

3

<p>Thank you Linger, i appreciate the help, if i score a 800 tomorrow morning, i owe it to you man</p>

4

<p>yep no problem, good luck to you tomorrow. I am also taking it and am a bit nervous lol.</p>

5

<p>Sorry if this sounds stupid but…I get the part where you have 4 in the first slot and 3 in the last slot, but where do you come up with 3/2/1 in the middle slots?</p>

<p>Wait I get it. THanks guy</p>