Official Quant thread for CAT 2013

MBA CAT 2024
5081
@audiq7 said:
A,B,C,D are 4 no.s. one of them is odd, one is even, one is a recurring decimal, one is an irrational sqr root of an odd no. AC divided by 6 gives an odd integer equal to BA while CD^2 gives an even integer to 5B. Find out the nature of the no.s
A-odd
B-recurring decimal
C-even
D- irrational sqr root of an odd no.
5082

@krum said:
yaar but aakash is from deep end, so he will be the slower guy
Exactly!!
5083
@deedeedudu yaar i think for the second leg you have switched the end, contradicting with the prblm
@krum 32hi hoga.
5084
@audiq7 said:
A,B,C,D are 4 no.s. one of them is odd, one is even, one is a recurring decimal, one is an irrational sqr root of an odd no. AC divided by 6 gives an odd integer equal to BA while CD^2 gives an even integer to 5B. Find out the nature of the no.s

A- odd
B- recurring
C-even
D- sq rt
5085
@krum said:
A-oddB-recurring decimalC-evenD- irrational sqr root of an odd no.
kaise approach kiya??
5086
@Brooklyn AC and Ab are integers. Only D can be irrational. D^2is an odd integer and CD^2 is even. so C is even. Since AC/6 is odd, A is odd. B remains, so its recurring decimal.
5087
@Brooklyn said:
kaise approach kiya??
A,B,C,D are 4 no.s. one of them is odd, one is even, one is a recurring decimal, one is an irrational sqr root of an odd no. AC divided by 6 gives an odd integer equal to BA while CD^2 gives an even integer to 5B. Find out the nature of the no.s

CD^2 - even integer - so D has to be sqr root
as D^2 is odd, C will be even to give even integer 5B
as AC is divisible by 6, A will be odd integer
5088
@krum said:
A,B,C,D are 4 no.s. one of them is odd, one is even, one is a recurring decimal, one is an irrational sqr root of an odd no. AC divided by 6 gives an odd integer equal to BA while CD^2 gives an even integer to 5B. Find out the nature of the no.s CD^2 - even integer - so D has to be sqr root as D^2 is odd, C will be even to give even integer 5Bas AC is divisible by 6, A will be odd integer
But then if B is a recurring decimal, then how can BA be an integer?
5089
@soumitrabengeri said:
But then if B is a recurring decimal, then how can BA be an integer?
if 5B can be an integer A can very well be 5 or some multiple of 5
5090
@krum said:
A,B,C,D are 4 no.s. one of them is odd, one is even, one is a recurring decimal, one is an irrational sqr root of an odd no. AC divided by 6 gives an odd integer equal to BA while CD^2 gives an even integer to 5B. Find out the nature of the no.s CD^2 - even integer - so D has to be sqr root as D^2 is odd, C will be even to give even integer 5Bas AC is divisible by 6, A will be odd integer
I too did same... But I guess something went wrong... If B is recurring then how can 5B be an integer?
5091
@krum said:
if 5B can be an integer A can very well be 5 or some multiple of 5
Agreed..that is the only solution possible..
5092

how many integral slon are possible for


a^2+2*b^2=1947
5093
@Ashmukh said:
how many integral slon are possible fora^2+2*b^2=1947
a=43 , b=7
a=37 , b=17
a=35 , b=19

5094
@krum said:
a=43 , b=7a=37 , b=17a=35 , b=19
hit n trial?? n ans is 16 u forgot - n a=5
5095
@adwaitjw said:
3 soln... As mentioned by @krum
16
5096
@Ashmukh said:
how many integral slon are possible fora^2+2*b^2=1947
16 solns?
b^2= 1947-a^2/2
a=+-43 , b=+-7
a=+-37 , b=+-17
a=+-35 , b=+-19
a=+-5, b=+-31
satisfies for integer values

krum bhai aur sabhi ko__/\_
5097
@viewpt said:
three soln?b^2= 1947-a^2/2a=43 , b=7a=37 , b=17a=35 , b=19ssatisfies for integer valueskrum bhai__/\__
16 hogi yaar :banghead:

http://www.wolframalpha.com/input/?i=a%5E2%2B2*b%5E2%3D1947&t;=crmtb01&f;=rc
5098

@Ashmukh said:
how many integral slon are possible fora^2+2*b^2=1947
a, b will not be multiple of 3

mod 8 =3
so only those numbers whose square leaves remainder of 1... ,1 + 1(2) =3

b =7 a = 43
b = 17 a = 37
b = 19 a = 35
b = 31 a = 5

16 solutions?




5099
@rkshtsurana said:
a, b will not be multiple of 3mod 8 =3so only those numbers whose square leaves remainder of 1... ,1 + 1(2) =3b =7 a = 43b = 17 a = 37b = 19 a = 35b = 31 a = 54 solutions?
ye kya funda lagya hai tune??
5100
@Brooklyn said:
hit n trial?? n ans is 16 u forgot - n a=5
Right... Didnt focused on 'integral' part n also missed one case...