June 1 2013 Math Thread

<p>750 is really steep. I expect the curve of 1 one 760~770. There were a lot of tricky questions. I get 800s on several SATs but this one was the trickiest.</p>

<p>Ratio for diameters of the two circle is 1:2?</p>

<p>@mpgh000 I’m fairly certain it said sphere:cylinder, as the sphere was inscribed inside the cylinder.</p>

<p>So 5 questions wrong would be a 700? Or what would that be?</p>

<p>mpgh0000</p>

<p>I’m 99% you’re wrong, I read the question several times because I was unsure. Also, why would they want the proportion of the cylinder to the sphere? I feel like it is much more usual to ask for the proportion of the smaller object to the larger one, that makes much more sense.</p>

<p>Man, I skipped that question. Totally did not even see it until too late. I could’ve done it too…</p>

<p>@NWskier I am so sure that it is 1.5 (3/2) though. I remember i did the problem a couple times.</p>

<p>I had 2/3 but changed it to 3/2 at the last minute because I had read the question incorrectly. I’m pretty sure it said to give the answer as the fraction of the volume of cylinder.</p>

<p>Here’s my contribution:</p>

<p>For the three line intersection:</p>

<p>3 intersecting lines produces 6 angles, 3 pairs of vertical angles.</p>

<p>Vertical angles are CONGRUENT.</p>

<p>THE SUM OF ALL THE DEGREES IS 360.</p>

<p>Which means: 2x+2y+2z=360</p>

<p>If you have one right angle, there must be another.</p>

<p>If you have two 90 angles:</p>

<p>180+2y+2z=360</p>

<p>2y + 2z= 180</p>

<p>Whichs means that the summon of the remaining two angles have to be 180. For obtuse angles, less than 180.</p>

<p>However since every angle comes in pairs, it’s impossible to even have over 2 right angles in 3 intersecting lines.</p>

<p>122 is the answer:</p>

<p>1001=2
1002=3
1003=4
1004=5
1005=6
1006=7
1007=8
1008=9
1009=10
1010=2
1011=3
1012=4
1013=5
1014=6
1015=7
1016=8
1017=9
1018=10
1019=11
1020=3</p>

<p>Add them up to get 122</p>

<p>What did you guys get for the 4x+5y+10y=3 question or was that an experiment.</p>

<p>What was the answer anyways, I didn’t find any of the answers right.</p>

<p>4x+5y+10z = 3
4x = 1
5y = 1
10z = 1
Solve, you get .55</p>

<p>It doesn’t make sense that the sphere is larger if it fits inside the cylinder.</p>

<p>You basically reversed the fraction.</p>

<p>Can someone explain the girl/clocks ahead problem? </p>

<p>I interpreted a watch 7 minutes ahead as being 7 minutes too early. For example right now it is 4:45 so a clock 7 minutes ahead would be 4:38. Is that wrong?</p>

<p>Wait, why does 4x=1
5y=1
10z=1</p>

<p>I didn’t remember the context of the problem. Was that experimental?</p>

<p>Answer to the clock question was 26 minutes.</p>

<p>It said 4x,5y, and 10z were positive integers.
They can only be integers if they all equal one.
It asked for x+y+z which = .55</p>

<p>Ahhhhh, never mind. I see the error in my logic.</p>

<p>Ugh what a stupid question to lose points on…so not worth it.</p>

<p>@rosin333 7 minutes ahead means that it is 7 minutes ahead. literally.</p>

<p>Was this 4x, 5y question on the experimental math section? I don’t remember having it</p>

<p>Dang it, I missed the integers part. That would have helped me alot</p>

<p>Once again sorry but did people get 0 or -20 for the problem with z + 10 and z - 10 or whatever</p>

<p>@Jazzed, it’s 0.</p>

<p>It said z = m+10
z-10 = m+10-10</p>