***Official December 9 ACT Math Thread****

<p>thats what i thought too....</p>

<p>o wait....so what is the answer then?</p>

<p>it makes sense that they gave you the length as radius. R for big radius, and r for small radius. ACT is so straight forward that if they wanted you to half them they would put D for diameter.</p>

<p>The answer would be:</p>

<p>1.57 (6.25 + 2.25 + 3.75) = 19</p>

<p>The answer I said like 20 posts ago</p>

<p>fandangoya, look at post #74 - thats how you do the problem, and the answer is 77</p>

<p>o wait so was I right or wrong</p>

<p>And how did u get 1.57(6.25+2.25+3.75)?</p>

<p>the answer is 77, so yeah. right i guess</p>

<p>They gave you the diameter and you were supposed to use the radius. I know because I missed the equivilent the day before on a practice test and I was proud of myself for not having made the same mistake again on the real thing.</p>

<p>o hmmm i remember the radius and not the diameter</p>

<p>ya, they gave you the diameter so fandangoya is correct. It is 19.</p>

<p>but it doesnt matter tho....they said volume equaled 1/3(pi)(h)[R^2+r^2+Rr]</p>

<p>and they said
h=1.5
R=5
r=3</p>

<p>so u just plus it in to the equation</p>

<p>i dont think it matters if it was the radius or the diameter...u just plug the things in</p>

<p>It hella matters because they never said R=5 and r=3, instead they gave you a picture of a stump with a line going ENTIRELY across the bottom of it saying 5 and another line going ENTIRELY across the top saying 3. </p>

<p>This is why you're not understanding. The values were not directly given, you had to find it from the picture by recognizing that a radius is not the entire length across as the numbers that were given.</p>

<p>werent the lines labeled R and r?</p>

<p>yes the values were labeled thats why i just plugged them in</p>

<p>They were labed on the top diagram but not on the stump one that followed.</p>

<p>thats because u were suppose 2 use the diagram to figure out the area of the stump</p>

<p>i think the main thing that messed ppl up was that R and r do not equal radiuses they are just variables</p>

<p>so what was the right answer?</p>

<p>i think its 77 but everyone has their different opinions....look at post 74</p>

<p>Its not 77. They gave you the diameter. If you think it doesn't matter, then that tells us you have no idea what you are doing. Read about radius and diameters first before you argue.</p>