1

any student who scores in the top 4% of students on the SMRT standardized exam. SMRT scores have a mean of 260 and a standard deviation of 22. What score does a student need to attain in order to receive the scholarship worked problem this way. 1.00-.04=.96 which gave me z-score of .8315. .8315*22+260=279 my worksheet says it should be 299. can someone tell me where I went wrong. thank you

barb
  • 65
  • The z-score for p=0.96 is $\approx1.75$. – callculus42 Oct 20 '14 at 20:38
  • this does not match my teachers worksheet answer of 299 and I don't understand how you came up with that answer. – barb Oct 21 '14 at 01:04
  • Look here: https://www.stat.tamu.edu/~lzhou/stat302/standardnormaltable.pdf where p is approximately 0.96. Do you find the corresponding z-value ? – callculus42 Oct 21 '14 at 01:11
  • I'm sorry but why would I look on the neg side and that is 169. I thought I understood how to work this but now I am confused. are you saying my teachers worksheet is wrong? – barb Oct 21 '14 at 02:52
  • I dont know, which worksheet do you use. Do you have a link to it ? It is really a table about the standard normal distribution ? You can work with the negative side of the distribution. It is $\Phi(-z)=1-\Phi(z)$, where $\Phi(\cdot)$ is the function of the standard normal distribution. In your case $\Phi(-z)=1-\Phi(z)\Rightarrow \Phi(-z)=1-0.96\Rightarrow \Phi(-z)=0.04$. Now you look at the linked table and find the z-value for p=0.04. This value is negative (-z). You have to take z. – callculus42 Oct 21 '14 at 04:11
  • Thank you after I post the last comment I seen what you were explaining, and I understand now. Thank you! – barb Oct 21 '14 at 06:24
  • Nice to hear, that is all clear. Your are welcome. – callculus42 Oct 21 '14 at 07:06

0 Answers0