1. ## About Mean, Median, Mode, Standard deviation

1. What is the mean, median, mode, and standard deviation for the following 13 items:
1,4,2,3,1,2,5,2,3,2,7,4,2

I solved this question:
1. mean is 2.92
2. median is 2
3. mode is 2
4. standard deviation is 0.49

My answers are correct? Your checks are needed and will be a big help for me.

2. There are two types of university entrance exams in US: SAT and ACT. Both of them are
standardized test. Midwestern schools use ACT for admission, rather than the SAT. You got a debate
with your friends which school has better undergraduates. One way to compare the quality of students is
to compare standardized test scores. Unfortunately, School A, like many Midwestern schools, uses the
ACT for admission, rather than the SAT, the test of choice for School B. The ACT has a top score of 36
and SAT scores can be converted into ACT scores using the equation ACT = -3.4 + 0.02339(SAT).
School B’s entering freshman class has a mean SAT score of 1230 and a standard deviation of 240.
School A has a mean ACT of 26.9 and a standard deviation of 5.4. Convert school B’s mean and standard
deviation of SAT scores to ACT scale.

Summary:
A uses ACT and A's mean is 26.9 and standard deviation 5.4
B uses SAT and B's mean is 1230 and standard deviation 240

My stuck point is that can B's mean or standard deviation just be inserted into the above equation, ACT= -3.4 + 0.02339(SAT) and converted into ACT scores? Thus, B's mean converted into an ACT score is 25.3697 and standard deviation 2.2136? Right? Your help is strongly needed. Please check my answers.

2. Originally Posted by ilovepsycho
4. standard deviation is 0.49

The only one I don't agree with. I get 1.7, how did you arrive at your answer?

3. Originally Posted by pickslides
The only one I don't agree with. I get 1.7, how did you arrive at your answer?
Through the formula: sqrt {{(sigma x^2 - (sigma x)^2/n}/n-1}
The others correspond to my answers?