Question

PLEASE HELP!!!!!!!!!

Answer 1

Scores on a statewide standardized test are normally distributed with a mean of 12.89 and a standard deviation of 1.95. Certificates are given to students whose scores are in the top 2% of those who took the test. This means that they scored better than 98% of the other test takers. Marcus received his score of 13.7 on the exam and is wondering why he didn’t receive a certificate. Show all work to determine whether Marcus’ score was high enough to earn a certificate. Write a letter to Marcus explaining whether or not he will be receiving a certificate. Include a brief summary of your statistical analysis in your letter.

Answer 2

@hartnn @jim_thompson5910 @nikato

Answer 3

µ is equal to the mean of normal curve, which in this case is 12.89. The Standard deviation or σ is 1.95, how much it’s separated by. The raw score, x, is 13.7 the original value of the variable.

You have to use the Z formula. \(\ \sf Z = \dfrac{13.7 - 12.89}{1.95} = \dfrac{0.81}{1.95} = 0.41 \)

You'll need a "Z-Table," on the Z table look for the tenth place of 0.4, then look at the hundredths place, 0.01. I got: 0.65910, times 100 equals 65.91%

Therefore, he's in the \(\ \sf \color{green}{top} \) (100-65.91)% = \(\ \sf \color{green}{34.09} \)% or in the \(\ \sf \color{blue}{bottom ~ 65.91} \)%

Answer 4

You can use that ^ to write your letter :3

Answer 5

THANK YOU!!!!!!!! :)

Answer 6

You're welcome ~