If x is to be selected at random from set T, what is the

Question

If x is to be selected at random from set T, what is the probability that x/4 -5  <  0?

(1). T is a set of 8 integers
(2). T is contained in the set o fintegers from 1 to 25, inclusive.

gmatornot · Answer

Is this E ?

We essentially want to find out if x<= 20

From 1, T could be any 8 integers

INSUFF

From 2, T is a subset if S where S = 1 - 25

Probability could be anywhere from 0 - 1
if T has 8 1's in which case Prob. = 1 
if T has 8 25's P = 0

INSUFF

Combined also seems INSUFF as the 8 integers could be the same integer....

zorro13 · Answer

E


X <= 0 

1: insuff (we can have any number here)

2: insuff (what happen if all the numbers are bigger than 20.....or less than 20?)

Together: Insuff the probability is different if we have 5 number bigger than 20 or all the numbers less than 20....

defenestrate · Answer

Wouldnt it be B. We know the set of numbers...Just like when doing probability for cards. If I am playing texas hold-em, just because there are only 10 cards in the deck does not change the probability from the cards that have been delt out that I do not know. 

We know that the number X is somewhere between 1-25...or is this a mistake?

haas_mba07 · Answer

OA is E... 

This one is from OG11.. DS section.

Futuristic · Answer

clearly E....seeing it was from haas, i though there was a trick....pretty simple this one:

basically need to find out prob of x <=20

From 1:

any 8 integers...INSUFF

From 2:
Only 5 integers are >20
So min of 3 integers in T will be <=20....but this no could be 4 5 6 ....which will change the prob....INSUFF

gk3.14 · Answer

I think the trap in B is that we could miss that "T is a subset of a set of integers from 1-25" The first time I read it, i assumed that T contained a set of integers instead of T is contained in a set of integers..

If x is to be selected at random from set T, what is the

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