<p>2007-2008 SAT Subject Test Preparation Booklet</p>
<p>For the math Section, how do you get the answers for 17, 22 and 25?</p>
<p>k i got 22 now, can someone help with 17 and 25?</p>
<p>there's more than one math section so post what number</p>
<p>and can u provide a link to the test?</p>
<p>i can't find a link, but its the official free booklet that the school hands out. i thought everyone has them</p>
<p>I only need help with this one now</p>
<p>The question is:
"When purchased, an automobile is valued at $15,000. Its value depreciates at the rate shown in the table above. Based ona least-squares linear regerssion, what is the value, to the nearest hundred dollars, of the automobile when t=4."
So the values of the table are: (0, 15,000) (1, 13,000) (2, 10,900) (5, 3,000)
answer= $5,600</p>
<p>To add to my PM, here's one more way of solving this.</p>
<h2>y = mx + b</h2>
<p>x1=0 | y1=15,000
x2=1 | y2=13,000
x3=2 | y3=10,900</p>
<h2>x4=5 | y4=3,000</h2>
<p>Mean x and y</p>
<h2>x<code>=2 | y</code>=10,475</h2>
<p>x1-x<code>=-2 | y1-y</code>= 4,525
x2-x<code>=-1 | y2-y</code>= 2,525
x3-x<code>= 0 | y3-y</code>= ...</p>
<h2>x4-x<code>= 3 | y4-y</code>= -7,475</h2>
<p>m = (Σ(x sub i - x<code>)(y sub i - y</code>)) / Σ(x sub i - x<code>)^2
m = ((-2)(4,525) + (-1)(2,525) + (0)(...) + 3(-7,475)) / ((-2)^2 + (-1)^2 + 0^2 + 3^2)
m = -2,428.57
b = y</code> - mx`
b = 10,475 - (-2,428.57)2
b = 15,332.14
y(x) = -2,428.57 x + 15,332.14
y(4) = 5,617.9
rounds to 5,600.</p>
<p>Edit.
Here's the link to the 2006-2007 Prep Booklet (2008-2009 Booklet has the same questions):
<a href="http://www.collegeboard.com/prod_downloads/prof/counselors/tests/sat/2006-07-SAT-subject-tests-preparation-booklet.pdf%5B/url%5D">http://www.collegeboard.com/prod_downloads/prof/counselors/tests/sat/2006-07-SAT-subject-tests-preparation-booklet.pdf</a>.</p>