# Statistics question driving me crazy!

#### pinkdaffodil

##### New member
Please if anyone can help me figure this question out I would greatly appreciate it.

The mean height of a group of 900 men is 74. The standard deviation is 4. What height would a man be if he is in the 95th percentile.

I don't even know where to begin. I keep thinking it has something to do with the z-score, but I'm not sure. Any help would be great.

Thanks

#### galactus

##### Super Moderator
Staff member
If he is in the 95th percentile, that means he is taller than 95% of the other men in the group of 900. That means he is in the top 5%.

Look up the z-score for .95 is 1.645.

Using $$\displaystyle 1.645=\frac{(x-74)\sqrt{(900)}}{4}$$ and solve for x.

#### pinkdaffodil

##### New member
Thank you so much!! I couldn't figure out where to start I got it now!