Search found 13 matches
- by carefreeamit
Sat Sep 06, 2008 6:57 pm- Forum: Problem Solving
- Topic: Smallest prime factor
- Replies: 3
- Views: 1463
Option 1-
3x + 1 = 3(4n + 2) + 1
= 12n + 7
Since 12n will always be even, 12n+7 will always be odd. i.e. not divisible by 0. --Sufficient
Option 2 - is not sufficient
Ans A
- by carefreeamit
Mon Aug 25, 2008 10:48 pm- Forum: Data Sufficiency
- Topic: Set 23 Q11
- Replies: 3
- Views: 1302
The question asked is to calculate ratio of Migration rate of Male to Female. ska7945, you are assumption is fine but you should calculate the rate. As per your assumption - rate of Male migration = 10/30 = 1/3 rate of female migration = 40/70 = 4/7 ratio of rate of male migration to female migratio...
- by carefreeamit
Mon Aug 25, 2008 7:26 pm- Forum: Problem Solving
- Topic: geese migration
- Replies: 5
- Views: 2207
for first 20M sales ratio is = 3/20
for next 108M sales ratio is = 9/108 = 1/12
% decrease = ((3/20) - (1/12)) * 100/(3/20)
= (4/60) * 100/(3/20)
= 400/9 = 44.44
Ans C
- by carefreeamit
Mon Aug 25, 2008 7:18 pm- Forum: Problem Solving
- Topic: pharmaceutical co.
- Replies: 1
- Views: 1275
statement 1 is not sufficient
statement 2 -
-x|x|> 0
since |x| is positive -x should also be positive i.e. x is negative.
take any negative value of x and substitute.
Ans B
- by carefreeamit
Mon Aug 25, 2008 12:23 am- Forum: Problem Solving
- Topic: Inequalities
- Replies: 6
- Views: 1588
25 is 13th odd number and 79 is 40th odd number.
sum of odd integers from 25 to 79, inclusive = sum of odd integers till 79 - sum of odd integers till 23 (remember 25 needs to be included in the total)
= 40^2 - 12^2
= 1600 - 144
= 1456
- by carefreeamit
Sun Aug 24, 2008 11:10 pm- Forum: Problem Solving
- Topic: the sum of first n consecutive positive
- Replies: 1
- Views: 1275
Since the ratio of infected v/s non infected is not known you can not find the final ratio.
option E.
- by carefreeamit
Sun Aug 24, 2008 10:50 pm- Forum: Data Sufficiency
- Topic: percentage problem..
- Replies: 3
- Views: 3596
Both a and b are not sufficient in themselves.
If ry < 1 then rate of z is greater than rate of y. From 1, we already know that rate of x is less than rate of y. So rate of x is less than rate of z too.
Ans C
- by carefreeamit
Sun Aug 24, 2008 10:37 pm- Forum: Data Sufficiency
- Topic: Robots X, Y, and Z
- Replies: 2
- Views: 3495
I got answer as D. If Mary persuaded n friends and they in turn persuaded n friends each then in the first round total collected was = 500 * n In the second round total collected was = 500 * n^2 Total collection = 500(n + n^2) Option a First round collection/total collection = 1/16 (500n)/500(n + n^...
- by carefreeamit
Sun Aug 24, 2008 10:22 pm- Forum: Data Sufficiency
- Topic: Mary persuaded n friends
- Replies: 1
- Views: 2720
There are multiple possible values x and y. So I started with a value where x and y will be same and then if y has to be greater than x then y has to be greater than sqrt 2 and x has to be smaller than sqrt 2.
- by carefreeamit
Sun Aug 24, 2008 4:36 pm- Forum: Problem Solving
- Topic: triangular region
- Replies: 7
- Views: 7500
I think answer is C.
I can think of 2^2 and 2^4 after which 2^n becomes larger than n^2.
Correct me if I am wrong.[/spoiler]
- by carefreeamit
Sun Aug 24, 2008 4:22 pm- Forum: Problem Solving
- Topic: For how many integers n is 2^n = n^2 ?
- Replies: 2
- Views: 7594
Area of square = 1/2 * base * height
which is 1/2 * x * y ..z has to be the hypotenuse
so 1/2 * x * y = 1
x*y = 2
now if x and y are same then x = sqrt 2 and y = sqrt 2
but x is smaller than y so y must be greater than sqrt 2.
Ans A.
- by carefreeamit
Sat Aug 23, 2008 9:11 pm- Forum: Problem Solving
- Topic: triangular region
- Replies: 7
- Views: 7500
4 digit number means it should be >= 1000 and <= 9999.
The first place can be taken by 2,4,6,8 i.e. in 4 ways.
The second, third & fourth place can be taken by 0,2,4,6,8 i.e. 5 ways each.
So the number of positive integers will be = 4*5*5*5 = 500
Ans C.
- by carefreeamit
Fri Aug 22, 2008 11:22 pm- Forum: Problem Solving
- Topic: 4-digit positive integers
- Replies: 3
- Views: 14154