Search found 9 matches
Re: probability
A group of 8 friends want to play doubles tennis. How many different ways can the group be divided into 4 teams of 2 people? Answer = 20475? possible teams: 12,13,14,15,16,17,18 23,24,25,26,27,28 34,35,36,37,38 45,46,47,48 56,57,58 67,68 78 7 + 6 + 5 + 4 + 3 + 2 + 1 = 28 choosing 4 teams out of 28 ...
- by axefx
Fri Jan 26, 2007 10:38 am- Forum: Problem Solving
- Topic: probability
- Replies: 8
- Views: 3658
Re: Question Test OG, maybe easy but...still
10 X (multiplied) If the question is: (5^11) * (4 ^ 11) = (2 * 10)^n Then the answer is n=11... (5^11) * (4 ^ 11) = (2 * 10)^n = (5 * 4) ^ 11 = (2 * 10)^n = (20)^11 = (20)^n i.e. n = 11 If the question is: (5^11) * (4 ^ 11) = 2 * (10^n) Then I don't know how to solve this question and will apprecia...
- by axefx
Thu Jan 25, 2007 12:10 pm- Forum: Problem Solving
- Topic: Question Test OG, maybe easy but...still
- Replies: 5
- Views: 3515
I assume the question asks for the unit digit of (a+2) ^ 2. if unit digit of a ^ 2 is 9 then unit place a should be 3 or 7 if unit digit of (a+1) ^ 2 is 4 then unit place can only be 8 => unit digit of (a+2) ^ 2 is 1 Hope this helps. can you please elaborate... your analysis seems to have a ton of ...
- by axefx
Thu Jan 25, 2007 11:57 am- Forum: Problem Solving
- Topic: don't understand the explanation in OG to this problem
- Replies: 3
- Views: 3278
Re: Section 6, question 25 1000 DS
Your post is missing the first condition... please repost.isisalaska wrote:Source: 1000 DS, section 6
25. If x ≠ 1, is y equal to x + 1?
(1)
(2) y2 = (x + 1)2
Why is not D?
- by axefx
Wed Jan 24, 2007 11:10 am- Forum: Data Sufficiency
- Topic: Section 6, question 25 1000 DS
- Replies: 3
- Views: 2136
d<1/4 Each is sufficient on its own. if d < 0.25, the value of d rounded to the nearest 10th would be 0.2 no matter what the value of h is (4,3,2,1 or 0), so thats sufficient. if h < 5, the value of d rounded to the nearest 10th would be 0.2 no matter what the value of h is (4,3,2,1 or 0), so thats...
- by axefx
Wed Jan 24, 2007 10:20 am- Forum: Data Sufficiency
- Topic: hundredths’ digit type of question
- Replies: 3
- Views: 3972
Re: PS 007
Answer is E. 17/52rajs.kumar wrote:PS 007
What is the probability that a card selected from a deck will be either an ace or a spade?
A. 2/52
B. 2/13
C. 7/26
D. 4/13
E. 17/52
4 aces and 13 spade cards... this is an OR condition so add the two probabilities:
4/52 + 13/52 = 17/52 !
- by axefx
Mon Jan 22, 2007 12:43 pm- Forum: Problem Solving
- Topic: PS question a Day
- Replies: 33
- Views: 11784
Re: probability
A group of 8 friends want to play doubles tennis. How many different ways can the group be divided into 4 teams of 2 people? Answer = 20475? possible teams: 12,13,14,15,16,17,18 23,24,25,26,27,28 34,35,36,37,38 45,46,47,48 56,57,58 67,68 78 7 + 6 + 5 + 4 + 3 + 2 + 1 = 28 choosing 4 teams out of 28 ...
- by axefx
Wed Jan 17, 2007 1:50 pm- Forum: Problem Solving
- Topic: probability
- Replies: 8
- Views: 3658
Would you mind explaining this:thankont wrote:I am not sure here but from n^x<n we see that it holds only when
0<n<1 and when x>1
from b we have that x=-1/2 so statement never holds (combining both)
so I would say --c--
"n^x<n we see that it holds only when
0<n<1 and when x>1 "
- by axefx
Wed Jan 17, 2007 12:56 pm- Forum: Problem Solving
- Topic: Math!
- Replies: 5
- Views: 4008
solution
Based on (a + b)^2 = a^2 + b^2 + 2*a*b
and (a - b)^2 = a^2 + b^2 - 2*a*b:
(1001^2 - 999^2) / (101^2 - 99^2)
= (1000 + 1)^2 - (1000 - 1)^2 / (100 + 1)^2 - (100 - 1)^2
= (1000^2 + 1^2 + 2*1*1000) - (1000^2 + 1^2 - 2*1*1000) / (100^2 + 1^2 + 2*1*100) - (100^2 + 1^2 - 2*1*100)
= 4000/400
= 10
- by axefx
Wed Jan 17, 2007 11:07 am- Forum: Problem Solving
- Topic: Can someone help me with this problem?
- Replies: 7
- Views: 4145