ANTOHER MATH QUESTION

Discus: SAT/ACT Tests and Test Preparation: October 2003 Archive: ANTOHER MATH QUESTION
 By Akaflex (Akaflex) on Monday, October 06, 2003 - 12:23 pm: Edit

An integer t is to be chosen at random from a set of 20 different integers. Which of the following must be equal to 1/2?

I. The probability that t is greater than the median of the integers

II. The probabilitiy that t is greater than the average of the integers

III. The probabiltity that t is odd

plz sum1 explain

 By Akaflex (Akaflex) on Monday, October 06, 2003 - 12:33 pm: Edit

HERES ANOTHER, ITS A QC

In 1995 there were 1.2 million people who became naturalized citzens of the US. This was an increase of more than 100 percent over p, the number of people who became naturalized citzens in 1994

Col A.

p

Col B.

.7 million

 By Xiggi (Xiggi) on Monday, October 06, 2003 - 01:09 pm: Edit

What is the median in a even series of number?

When there is an even number of values in the data, the median is the average of the middle two values. Half the numbers in the data set are supposed to be less than or equal to the median, and half the numbers in the data set are supposed to be greater than or equal to the median.

Imagine the following set -the numbers are NOT consecutive, simply different:

2 4 6 8 10 12 14 16 18 20
22 24 26 28 30 32 34 10000 10002 10004

What could you say about average and odd numbers?

 By Xiggi (Xiggi) on Monday, October 06, 2003 - 01:13 pm: Edit

For the other one:

If p + 100%p = 2p

If p was 700,000 in 1994, the population would be at least 2p+1 or 1,400,001. Since the 1995 population is 1,200,000, the p of 1994 had to be smaller than 600,000.

B is bigger.

 By Laniman (Laniman) on Monday, October 06, 2003 - 01:27 pm: Edit

Consider the median: Say I have 1,2,3,4 - 2.5 would be my median. The probability of t being > than 2.5 is 1/2
The Average: Say I have 5,6,7,8,9,10. Average 7.5. Again 1/2
NOTE: Even though I'm only considering 4/6 intergers each time, It would hold true for 20 integers also.
As for the probability being odd, I'm assuming 0 is neither odd nor even. Hence its <1/2

 By Laniman (Laniman) on Monday, October 06, 2003 - 01:30 pm: Edit

And as for the second one. B.

 By Xiggi (Xiggi) on Monday, October 06, 2003 - 01:31 pm: Edit

?

 By Laniman (Laniman) on Monday, October 06, 2003 - 01:37 pm: Edit

I'm sorry about the first post. Didn't consider an even number of nos. Edited for even number of nos. :|

 By Xiggi (Xiggi) on Monday, October 06, 2003 - 01:40 pm: Edit

Laniman~

What are the odds that NONE is an acceptable answer on the SAT test?

The options were probably, 1,2,3, 1 and 2, 2 and 3 or something like that.

Anyhow, please read my answer again. I am afraid that your example of 5 integers was poorly chosen. 1-5 is NOT representative of the problem at hand. You need to use ALL the elements of the stated problem and need an even pool of numbers.

The answer is -without a doubt- A.

 By Xiggi (Xiggi) on Monday, October 06, 2003 - 01:41 pm: Edit

Simultaneous posts

 By Laniman (Laniman) on Monday, October 06, 2003 - 01:47 pm: Edit

:P

 By Laniman (Laniman) on Monday, October 06, 2003 - 01:52 pm: Edit

Ahh..pool is the word I was looking for. Even number of numbers..sheesh