SOLUTION: In an intelligence test administration to 1000 student the average score is 42 and the standard deviation is 24. The score are normally distributed.
1. Number of student whose sco
Algebra ->
Probability-and-statistics
-> SOLUTION: In an intelligence test administration to 1000 student the average score is 42 and the standard deviation is 24. The score are normally distributed.
1. Number of student whose sco
Log On
Question 190008This question is from textbook
: In an intelligence test administration to 1000 student the average score is 42 and the standard deviation is 24. The score are normally distributed.
1. Number of student whose score exceed 58.
2. Number of student whose score lie between 30 & 66.
3. If 40% student have failed in this intelligence test what is the score below which they have failed.
Given that p(0This question is from textbook
You can put this solution on YOUR website! In an intelligence test administration to 1000 student the average score is 42 and the standard deviation is 24. The score are normally distributed.
1. Number of student whose score exceed 58.
z(58) = (58-42)/24 = 2/3
P(z > 2/3) = 0.25249
# of students with score above 58 = 0.2525*1000 = 253
-----------------------------------------------------------
2. Number of student whose score lie between 30 & 66.
P(30 < x < 66)= P(-1/2 < z < 1) = 0.5328
# of students with score between 30 a dn 66 is 0.5328*1000 = 533
-----------------------------------------------------------
3. If 40% student have failed in this intelligence test what is the score below which they have failed.
The z-score corresponding to 40% is -0.2534
Use z = (x-u)/s to solve for "x".
-0.2534 = (x-42)/24
x-42 = -6.0803
x = 48.08 (they failed because they had a score below 48.08
==============================================================
Cheers,
Stan H.
======================
(