BB Math Practice Test 7 Sect 5: Q #6, #14 p. 792, 794

<p>Hey I want to know what is the quickest, and easiest way that you would recommend I solve this math question on the SAT:</p>

<p>6) If n is a positive integer and (n+1)/2^n = 1/2, then n=</p>

<p>a)1
b)2
c)3
d)4
e)5</p>

<p>I plugged in the answers one by one, is there a quicker way?</p>

<p>14) Let the function h be defined by h(t) = 2(t^3-3). When h(t) = -60, what is the value of 2-3t?</p>

<p>the answer is b)11. Is there some kind of quick shortcut way to do this?</p>

<p>I plugged -60 in for h(t), solved for t, and then plugged that back in to 2-3t. I think there is probably a faster trick if you can see something...but what?</p>

<p>Thanks for your help=)</p>

<p>I'm confused. Is that (n+1)/(2^n) = 1/2 OR ((n+1)/2)^n = 1/2 ??</p>

<p>One way would be to simply use a graphing calculator. In mine, I can simply enter an equation ... and it gives me the solution. :)</p>

<p>Start with C, if the answer is bigger than necessary, cross out A, B, and C.
Try D, if its correct, then your done. If it's not, then your still done (E would be the answer)</p>

<p>It took me 10 seconds solving the second problem.</p>

<p>2(t^3-3)=-60
(t^3-3)=-30
t^3=-27
t=-3</p>

<p>plug it in
2-3(-3)=11</p>

<p>I didn't use a calculator. If you knew the cube root of 27, it would have saved probably 3 seconds of pressing it into the calculator.</p>

<p>I don't use the calculator for questions that are this simple either, I was just saying it's another way of doing it.</p>

<p>But honestly, is there no way of doing the first one except by plugging in?</p>