Thread: Statistics problem

1. Statistics problem

Only have the following info on a population:

mean = 10
SD = 2.8
median = 10

BAsed on this info..what is probability that a randomly selected individual has a value of 10 or more i.e. P(x>=10)?

I know I need to find a z-value (I think) to look up this probability in a normal distribution table but what value do I look for? I don't think the answer is as simple as 0.50 (50%) given that the mean=median=10. Is it?

Thanks for your help.

2. Originally Posted by simash4
Only have the following info on a population:

mean = 10
SD = 2.8
median = 10

BAsed on this info..what is probability that a randomly selected individual has a value of 10 or more i.e. P(x>=10)?

I know I need to find a z-value (I think) to look up this probability in a normal distribution table but what value do I look for? I don't think the answer is as simple as 0.50 (50%) given that the mean=median=10. Is it?

Thanks for your help.
1. You are not told that this random variable is normally distributed so you
should avoid making that assumption.

2. You are told that the median is 10, so irrespective of the distribution the
probability that a randomly selected individual has a value >10 is 0.5.

RonL