milanjoshi

thanks ss and vinay .. vinay ..can u tell me exactly what is the quantity in col a and col b in 2nd problem (bills )? vidu .. x* represents the greatest integer less than or equal to x , so x* = 1 x$ represents the least integer greater than or equal to x , so x$ =2 ( here the condition is greater than or equal to x .... and can't i take x$=1 since it is equal to 1?) thanks milan

*From the set of 6 letters a,b,c,d,e and f there are 20 different 3 letter subsets that could be selected col a the number of 3 letter subsets that include the letter F col b 10 the general approach abf acf adf aef bcf bdf bef cdf cef def making total of 10 and the answer is C . could anyone suggest the quick approach ?? * This was the question that i had posted a couple of months back and again am recollecting . Scheel explained it marvelously ,but still i am not able to get the logic .i know the answer is C but could anyone explain me the exact result from the two columns using some formula rather than comparing ? # Seven $1 bills are to be distributed among mr A,B and C so that each person receives at least 1$ column A number of ways to distribute the bills col B total no of ways to distribute bills so that at least 1 person receives at least 3$ # x* represents the greatest integer less than or equal to x and x$ represents the least integer greater than or equal to x if x =1.4 col a (x* + x$)/2 col b 1.4 given that 1.4* represents the greatest integer less than or equal to 1.4 that is 1 (greatest int. with condition) and 1.4$ represents the leaset integer greate than or equal to 1.4 that is 1 (least int. with condition). resulting B the answer. but the answer provided is A , and i wonder how? if A is to be the answer "or equal to " clause must be removed from the question .:) thanks in advance guys.... -milan

hi kv seems answer for q1 is D ... since the height is not given -milan

1. col a surface area of a cone of radius 12 col b surface are of a cone of radius 13 What is the surface area of cone?? 2. What is the total number of different 5-digit numbers that contain all of the digits 2, 3,4,7 and 9 and in which none of the even digits occur next to each other? (A)72 (B)100 ©120 (D)60 (E)48 arrangement of 2 and 4 2-4-- 2--4- 2---4 -2-4- --2-4 --2-4 4-2-- 4--2- -4-2- 4---2 -4--2 --4-2 12 ways and arrangement of remaining 3 digits is 3! making 72 . Is A 'A' correct ? 3. a rectangular box of dimention (2*8*20)cubic inch is to be completely wrapped with paper. If a single sheet of paper is to be used without patching, then the dimensions of the paper could be (A)17 in by 25 in (B)21 in by 24 in ©24 in by 12 in (D)24 in by 14 in (E)26 in by 14 in is A the correct answer ? 4. A store currently charges the same price for each towel that it sells. If the current price of each towel was to be increased by $1, 10 fewer of the towels could be bought for $120, excluding sales tax. What is the current price of each towel? (A)$ 1 (B)$ 2 ©$3 (D)$ 4 (E)$ 12 what is the solution for this problem?

thanks ............let me start up another thread

Please correct me with these problem from ddd.net if i am wrong and vidu .. i had seen your post regarding answer keys for these problem . Please let me know if there is .. thanks 1.How many positive integers less than 20 are equal to the sum of a positive multiple of 3 and a positive multiple of 4? (A) Two (B) Five © Seven (D) Ten (E) Nineteen multiples of 3 are 3,6,9,12,15,18 multiples of 4 are 4,8,12,16,20 sum of multiples 7,11,15,19,10,14,18,13,17,16 making total of 10 but there are more multiples of 3 and 4 ,for instance 3*1/3=1 3*2/3=2 4*1/4=1 4*2/4=2 resulting more than 10 total sum of multiple and answer is more than 10 that is D 2. In a soccer league, If there were 10 teams and each team played each of the other teams 16 times, how many games did each team play? (A) 144 (B) 140 © 134 (D) 125 (E) 106 is it C? 3. In a certain country, a person is born every 3 seconds and a person dies every 10 seconds. Therefore, the birth and death rates account for a population growth rate of one person every a. 3 1/3 sec b. 4 2/7 c. 7 d. 11 2/3 e. 13 is it a?

hey vinay.... ya.... most of the prob are from powerprep 3.0 milan

oooookkay now i have these in shape .......... thank u -milan

# vinay After some guessings, i think the answer given by ETS is correct for q2 .... 99 10,11,12,13,14 as well as -10,-11,-12,-13,-14 so overall 10 different values .. But i can't still figure out the technique that is to be used for these kinda problem .. if sqrt(7) 3 4 5 8 10 here .. i have tried .. i) squaring on all sides we get 7 so the possible numbers are 3,4,5,6 and yes answer is B .. but if i follow the steps of previous problem then there are 8 possible values for x 3,4,5,6 -3,-4,-5,-6 ii) sqrt(7) sqrt(7)=2.6__(approx. 3) sqrt(37)=6.2__(approx 6) so there are 4,5 . supposing that i took an inequality as 2 AND THIS IS REALLY MAKING ME VEXED!!!

1. a certain box contains 6 marbles - 3red,2blue,1 white .If three marbles are to be selected at random from the box, what is the probability that no red marble will be drawn ? 1/2 1/6 1/18 1/20 1/60 heres what i got ... total marbles = 6 probability of not getting red in first trial = 3/6=1/2 probability of not getting red in second trial = 2/5 probability of not getting red in third trial = 1/4 hence 1/2*2/5*1/4 = 1/20 . D is the answer and it is . But, can anyone explain why is the alternate method not working ? probability of getting red in first trial = 3/6=1/2 probability of getting red in second trial = 2/5 probability of getting red in third trial = 1/4 not getting any red =1 - 1/2*2/5*1/4 =19/20 ?????????? 2. If n is an integer and 99 2 4 6 8 10 I think n could have 10,11,12,13,14 different values .... how come answer is E that is 10??? 3. One(exterior) of the two circle with same center has radius twice than that of interior cirle. col A the probability that a point selected at random from the larger circular region will lie in the region between ext. and int. circles col B 3/4 Please explain for this probability solution.. thanks in adv.

thanks DP for correcting me milan

hmmmmmmm, i got it !! here another 1) From the even numbers between 1 and 9 ,two different even numbers are to be chosen at random.What is the probability that their sum will be 8? 1/6 3/16 ¼ 1/3 ½ The even nos are 2 4 6 8 2 and 6 are only two integers whose sum is 8 and we are to find the probability to choose 2 and 6 from 2 4 6 8 Soln 1 the probability of 2 and 6 is 2/4 =1/2 Soln 2 The probability of not getting 2 in first choose is ¾ and the probability of not getting 6 in second choose is 2/3 Hence probability of getting both 2 and 6 is 1-(3/4*2/3) = 1/2 I don’t know the answer . is ½ the answer????? 2) Two trains are 120miles apart and are traveling toward each other at a constant rate of 30 mph and 40 mph respectively .How far apart will they be exactly 1 hour before they meet? 10miles 30 40 50 70 here is my sol. Lets suppose A (30mph) and B(40mph) are two trains and ‘t’ be the time when both trains meet. x be the distance travelled by A at time t , then 120-x is the distance traveled by B at time t x=30t -----1 120-x=40t--------2 from 1 and 2 t=1.7 hrs Hence A has traveled 51 miles and B has traveled 69 miles from their starting position till they meet . 1hour before ..that is t=1.7-1=.7 hrs A would travel 30(.7)=21 and B would travel 40(.7)=28 miles from their original position Hence A and B are (51-21)+(69-28) = 71 miles away before they meet..so E is the answer. Could anyone suggest more easier and faster method to solve this kinda problem ? 3) A number is randomly selected from the set of integers from 1 to 40 inclusively Col A Probability that the no selected is an odd multiple of 3 Col B Prob. that the number selected is an even multiple of 3 There are 7 odd and 6 even multiple of 3 making col A 1/7 and col B 1/6. Col B is greater. Am I right ?

1) how many positive numbers can be expressed as a product of 2 or more prime numbers 5,7,11,13 if no one product is to include the same prime factor more than once ? 8 9 10 11 12 2) the reflection of any positive integer can be obtained by reversing its digits ,eg reflection of 123 is 321 . The difference between 5 digit integer and its reflection is divisible by which of the following integer 2 4 5 6 9 answer to q1 is 11 and q2 is 9 ….. but how??????

vinay thanks ........ i got it milan

hi vidu, ya... it helped but here is my solution for 2 of them there are 8*2-2 = 14 ways for remaining 6 there are 6! ways total ways : 6! * 14 = 10080 but what if the question goes like this : how many ways can 8 people be arranged in a round table of 8 seats if 2 of them insist on sitting next to each other? circular arrangement is making me tooooo confused !!!! thanks for your great help .. vidu and vinay -milan