Official Quant thread for CAT 2013

MBA CAT 2024
30651
@catahead said:
1)135
30652
@catahead said:
1 - c
2- b(edited) ??
30653
@zuloo said:
could you explain the bold part?


25^59/9
E(9)=6
so (25^6)^9/9*25^5/9
pehla wala part will give 1 so left with 25^5/9
implies 7^5/9
49^2*7/9
4*4*7/9
rem=4

30654
@catahead said:
Q-3 C
30655
@catahead said:
1. 135 ?
2. x - y + 1 = 0 ?
30656
@catahead said:
Q-1 C - 135 Degree
30657
@catahead said:
Q1.c ?
30658
@catahead said:
C B C
30659
@mailtoankit yup...its correct...how ?
30660
@mani0303 said:
81 pencils are to be distributed among 14 students. What is the minimum number of pair of students that must have got the same number of pencils?
minimum 2 students?
pair 1 :)
30661
@abhishek.2011 said:answe kya haii
minimum 2 students?
30662
@nits_rocker said:
if A= 10! + 12! +14! + 16!......100!,highest power of 2 in A?
10/2 +10/4 +10/8=8
30663
@floamiya said:
DSInformation in which of the following statements is sufficient to find the unit digit of2^(a-3)+ 3^(a-1)+ 8^(a+1)+ 7^(a+3) ...???I. the unit digit of a is 4II. The tens digit of a is odd.a] Statement I onlyb] Statement II onlyc] Both statements I & IId] cannot be found even by both statements.
statement 1 only ????
30664

"In how many ways can 72 be written as a product of two co-prime numbers'?


one of them will be 9X8, the other 72X1?
30665
@veertamizhan said:
"In how many ways can 72 be written as a product of two co-prime numbers'?one of them will be 9X8, the other 72X1?
Yeah...72 is basically having 2 distinct prime factors. If there are n distinct prime factors, it can be written as the product of two co-primes in 2^(n-1) ways.

regards
scrabbler
30666
@catahead said:
for 1st
300 m from the starting point

for second
4!/4^4=3/32
30667

"How many primes cannot be expressed as a difference of squares of two natural numbers"?

30669
@veertamizhan said:
"How many primes cannot be expressed as a difference of squares of two natural numbers"?
One.

Any odd number can be expressed as the difference of consecutive squares.

regards
scrabbler
30670
@scrabbler

In how many ways can four persons be selected from ten persons sitting around a circular table such that none of the selected person were sitting next to each other previously?

A. 10
B. 15
C. 25
D. 100
30671
@scrabbler sir, thanks.