May 2010 Math SAT Thread

Test Preparation SAT Preparation
621

<p>Yeah, viggy’s solution in post #599 to the median question is probably simplest. I believe the numbers were as follows, with the y-axis numbers (number of cars) in the top row and the x-axis numbers (gas mileage) in the bottom row.</p>

<p>40 50 40 30 10
25 26 27 28 29</p>

<p>There were therefore 170 total cars. That means there are 85 cars less than (to the left of) the median gas mileage and 85 cars greater than (to the right of) the median gas mileage. If you listed all of the cars in numeric order, you’d have forty 25’s, then fifty 26’s, then forty 27’s and so on. Both the 85th and 86th cars (between which the median lies) will fall within those cars with gas mileage of 26 (the last car with 26 mileage will be the 90th car…the 91st car would be where the 27’s begin).</p>

622

<p>if you looked closely at the graph, there was a point on the y-intercept. my estimation was 7 at first, but then i noticed that they had plotted the point 0,13ish</p>

623

<p>I plugged in all the points on my calc (stat -> regression) and got something like y=-6.86a+12.96 (something close to -7a+13)</p>

<p>For the median problem, I just started to cross off biggest to smallest. Whatever I ended up with was the median (26).</p>

624

<p>for the last grid in (I think)
would 9522 work?</p>

<p>9=5+2+2
9x5x2x2=180</p>

<p>so multiple of 10 and all…</p>

625

<p>^it would, but the problem stated that all the #s were different.</p>

626

<p>“I plugged in all the points on my calc (stat -> regression)…”</p>

<p>Chirst, it’s the definition of a function. Any pair of values of x and y would work.</p>

627

<p>Any guesses as to what -3 grid and -1 MC would be? :[
So many careless mistakes.</p>

628

<p>^Agreed. I found that quite funny. I am disappointed that I won’t be a member of the 800 club.</p>

629

<p>I’m quite sure it was Jill to Alicia or whatever her name is.</p>

<p>3:2</p>

630

<p>Does anyone remember the grid-in question that yielded 72 as the result?</p>

631

<p>it was teh number of packing the last day</p>

632

<p>Thanks. One more question. On the list, there are 2 (3/2) answers. One is the ratio between the runners, what was the first?</p>

633

<p>I think it sis 4 times 3/2 =6</p>

634

<p>what was the answer to the question with a circle(but without the outer lining, so it was just the angles) cut up to like 6-7 angles…there were like 3-4 X’s and Y’s…
some of the choices were x+y=120 or x=y…what was it? i put x=y but i don’t know for sure…</p>

635

<p>is that the one with angles x,y and w ?</p>

636

<p>It was not with x, y, and w. I remember getting x=y. Was that one experimental?</p>

637

<p>i honestly don’t remember if it was section 3 or not…but i have a feeling that it wasn’t…</p>

638

<p>cannot remember a question with x=y. maybe experimental</p>

639

<p>Were all experimetals section 3? I had 4 math sections but cr 3rd</p>

640

<p>I had writing as 3rd section</p>