Official Quant thread for CAT 2013

@The_Loser said:
why when right angled.?
Height max for a given base...take the 10 as base, draw an arc of 7 from one end, see where max height will come....it is when the 7 is perpendicular to the 10...

regards
scrabbler

1,2,3,7... seq is generated by adding 1 to first term to get second, adding 2 to second term to get third, adding 3 to third term to get the fourth.. so on
value of 156th term.??

12090
12091
12089
12094
12088

@The_Loser said:
why when right angled.?
Area = 1/2 * a * b * sin C
Maximise sin C = 1 at C=90

a billiard ball is hit at 45 degree angle from the corner of 6 by 8 foot billiard table
How many times ball rebound off an edge of the table before landing into corner>?
5,6,7,8,2. ?

@The_Loser said:
1,2,3,7... seq is generated by adding 1 to first term to get second, adding 2 to second term to get third, adding 3 to third term to get the fourth.. so onvalue of 156th term.??1209012091120891209412088
1, 2, 4, 7 hoga na?

If so, 12091?

regards
scrabbler

@scrabbler said:
1, 2, 4, 7 hoga na?regardsscrabbler
sry typo. 1, 2, 4 , 7
@scrabbler said:
1, 2, 4, 7 hoga na?If so, 12091?regardsscrabbler
explain. :-)
@The_Loser said:
a billiard ball is hit at 45 degree angle from the corner of 6 by 8 foot billiard tableHow many times ball rebound off an edge of the table before landing into corner>?5,6,7,8,2. ?

5, by drawing figure roughly...

regards
scrabbler

@The_Loser said:
a billiard ball is hit at 45 degree angle from the corner of 6 by 8 foot billiard tableHow many times ball rebound off an edge of the table before landing into corner>?5,6,7,8,2. ?
5 hoga

i drew a diagram and figured it out
@The_Loser said:
explain.
Well....series was quadratic....so found equation...1/2 * (x^2 - x + 2) then substituted x = 156.

Before that figured that it should be odd (looking at pattern) but 3 options got eliminated and 2 remained :(

regards
scrabbler

@joyjitpal said:
bhai i have a query heretime is constant hereso we can say they are travelling in opposite direction they will together cover the distance in the ratio of the speedisnt it?
yeah and if they were travelling in the same direction then the distance covered and also the relative speed will be different.. in a simple case in the first round they wil travel distance "d" in the second round they wil travel a distance of "2d"
@scrabbler said:
Well....series was quadratic....so found equation...1/2 * (x^2 - x + 2) then substituted x = 156.Before that figured that it should be odd (looking at pattern) but 3 options got eliminated and 2 remained regardsscrabbler



bhai 1/2 * (x^2 - x + 2) ye kaise mila tereko?

@scrabbler said:
5, by drawing figure roughly...regardsscrabbler
bhai agar isme right spin ya left spin ya screw back karke mare toh bhi 5 rails pe lagke pot hoga? :P
P.S sorry for spamming but i am a snooker addict so i was tempted to post something like this :P
@joyjitpal said:
bhai 1/2 * (x^2 - x + 2) ye kaise mila tereko?
1, 2, 4, 7....first level difference is:
1, 2, 3, 4...so second level difference is:
1, 1, 1, 1...so this is a quadratic equivalent (continuous function mein "second derivative constant" ka equivalent)

So try ax^2 + bx +c
For x = 1 a+b+c = 1
For x = 2 4a+2b+c = 2

For x = 1 9a+3b+c = 4
solve for a, b, c

I saved one step by recognising that if the second level difference is 2, it is a quad with a = 1. If second level diff is 1, therefore, a must be 1/2 and so only had to find b and c.

regards
scrabbler

@scrabbler said:
Seems good. I did something different, took a line from D parallel to BE.....and somehow got that AC is divided into 3 equal parts...regardsscrabbler
bhai can you help me out by supporting your statements with geometric figure.. as it is easier to understand then
@iLoveTorres said:
bhai agar isme right spin ya left spin ya screw back karke mare toh bhi 5 rails pe lagke pot hoga? P.S sorry for spamming but i am a snooker addict so i was tempted to post something like this
No, but sometimes more and sometimes less, roughly a Poisson distribution. I did a Monte Carlo simulation to 5 million iterations and the resultant mean value was 4.9857. Hence 5.

P.S. Sorry for spamming but I am a maths addict so I was tempted to post something like this.

regards
scrabbler

@iLoveTorres said:
bhai can you help me out by supporting your statements with geometric figure.. as it is easier to understand then
Will try. Lappy is in office and this comp tends to slow/crash if I run too many things :D

regards
scrabbler

@scrabbler said:
1, 2, 4, 7....first level difference is:1, 2, 3, 4...so second level difference is:1, 1, 1, 1...so this is a quadratic equivalent (continuous function mein "second derivative constant" ka equivalent)So try ax^2 + bx +cFor x = 1 a+b+c = 1For x = 2 4a+2b+c = 2For x = 1 9a+3b+c = 4solve for a, b, cI saved one step by recognising that if the second level difference is 2, it is a quad with a = 1. If second level diff is 1, therefore, a must be 1/2 and so only had to find b and c.regardsscrabbler
all the terms are in form :-
1
1+1
1+1+2
1+1+2+3
1+1+2+3+4
.
.
.
1+1+2+3+4.....................+155
1+(155*156/2)
12091
plz correct me if wrong
@iLoveTorres said:
bhai can you help me out by supporting your statements with geometric figure.. as it is easier to understand then
See this?

regards
scrabbler

@scrabbler said:
See this?regardsscrabbler
bro how did you get that the height to point "Y" is half that of height to point "D"?