Calling Out All Math Geniuses !!

<p>So I've gone through some math sections in the blue book and i need some clarifications regarding some problems. AKA I NEED YOUR HELP!! PLEASEE!! I beg you to help me understand these problems. And I will reallly really really appreciate it if you do. Here they are:</p>

<p>(All from blue book...if a new 1 came out its not the new one)</p>

<p>pg397 # 7</p>

<p>pg398-99 #'s 11,12,13,&16 </p>

<p>pg400 # 19</p>

<p>pg408 #5 pg406 #7 </p>

<p>pg411 #13,&14
pg412 #17 & 18</p>

<p>pg427 #16
pg460 #4
pg462 #14 pg 463 #15 pg464 #19 </p>

<p>pg473 # 8
pg 475 #15 & 16</p>

<p>Especially pg 476 17 & 18</p>

<p>pg488 #5</p>

<p>pg490 #11 &12</p>

<p>pg 491 #15</p>

<p>pg521 # 14 pg522 # 15 </p>

<p>pg 523 # 20
pg532 # 6 & 8</p>

<p>pg534 #14
pg535 #16</p>

<p>pg549 # 6 & 9</p>

<p>pg551 #'s15 17</p>

<p>pg 584 # 9 12</p>

<p>pg 585 # 16</p>

<p>pg 586 # 18 pg587 19, 20</p>

<p>pg 595 # 4 (i got E)</p>

<p>pg 596 # 8</p>

<p>pg599 # 17 & 18</p>

<p>pg 612 # 6</p>

<p>pg 515 #s 15 & 16</p>

<p>and finally pg653 # 3,5 AND pg 656 # 12 AND pg 657 's 17 & 18 -___-</p>

<p><a href=“http://talk.collegeconfidential.com/sat-preparation/339734-consolidated-list-original-blue-book-math-solutions.html[/url]”>http://talk.collegeconfidential.com/sat-preparation/339734-consolidated-list-original-blue-book-math-solutions.html&lt;/a&gt; </p>

<p>did you check that? </p>

<p>if you have and you’re questions aren’t solved in there than i’ll explain them to you</p>

<p>Most of them are not there. Please if you can just provide some explanations. If you have time of course. </p>

<p>I will appreciate it. Thanks. =).</p>

<p>397 -7: since rstv=1 you can determine that neither r nor s nor t equals 0 thus when stuv=0 the only new factor is u, and because of the zero product property - u = 0</p>

<p>398 - 11: curved path equals half the circumference of each of the semicircles but since they have the same radius it is simply the full circumference of one of the smaller circles; since the big circle has a circumference of 36pie: radius equals 18: radius of the smaller circle is 9 - circumference is 18pie
398-12: linear function: 1,24 is the midpoint of 0,a and 2,b thus the total distance between the points is 48 - c
398-13- pattern repeats after 4 sequences, thus divide 55/4 and the remainder is the place in the sequence where the 55th term is: remainder is 3 thus the answer is -5
399:16: volume of right cylinder = pie * R^2<em>h in this case 2x^3</em>pie - thus the only possible answer that has that volume is E has the same volume - length times width tmes height equals pie*2x^3
400-19-for these problems - most effective to plug in numbers and see - the acceptable deviance is 1/8 as shown by the question; thus the inequality has to be less than, so choices a and b are eliminated, the difference must be less than 1/8 so e is eliminated, and if you try out numbers you will find that c is the only answer that works
476 - 17 - this is a pretty tough problem but if you take it step by step it is not that difficult: so, you start at 7:30 and count the number of chimes: 13 clocks total chime once on the half hour so 13 chimes at 7:30, 8:00 - 10 clocks chime 8 times at 8 o clock equals 80 chimes plus 5 clocks that chime 8 times at 8 so 40 plus 3 that chime once at 8 - on the hour, total so far is 136, 8:30 is the same as 7:30 so plus 13 equals a grand total of 149.
476-18-this is a permutation problem - order does matter, think of it as 5 slots: 4 options for slot 1 on the left end, 3 options for slot 2 on the right end, 3 options for slot 3 in the middle 2 options for slot 4 in the middle and 1 option for slot 5 in the middle, multiply and you get 72.
sorry but that’s all i have time for</p>