Question

Scores on an english test are normally distributed with a mean of 33.6 and a standard deviation of 8.3. Find the 41st percentile?

Answer 1

Go to the Z tables for standard normal distrobution and find the normalized value for 0.41. You have to interpralte because the closest value is between -0.22 and -0.23. So Z=approx-0.225. From here you can solve for x using algebra. (x-33.6)/8.3=-0.225. Therefore x=(-0.225*8.3)+33.6=31.7325