Q1

Consider the data 1,7,5,2,2,7,13,10, 3,11,3,15.

1. Calculate N =
2. Calculate X=
3. Calculate X²=
4. Calculate estimated population variance=

Q2

In a test, teacher finds that the class average is 30, and standard deviation is 6. Teacher wants to move the average to 60 and at the same time increase the variability among the scores.

1. What is the new standard deviation for the class after this transformation?
2. Sean's mark on the test is 32. What is his new grade after the transformation?
3. Bob's mark on the test is 39. What is his new grade after the transformation?

Please explain the steps!!!! Im bad at it!

Q3

In a test, teacher finds that the class average is 53, and standard deviation is 6. Teacher wants to move the average up to 68 without increasing the variability among the scores.

1. What is the new standard deviation for the class grades after this transformation?
2. Sean's mark on the test is 55. What is his new grade after the transformation?
3. Bob's mark on the test is 40. What is his new grade after the transformation?