Question

A true-false test consists of 20 questions, each of which has one correct answer: true, or false. One point is awarded for every correct answer, but one point is taken off for each wrong answer. Suppose a student answers every question by guessing at random, independently of other questions. Let S be the student¢s score on the test.Find E(S), SE(S), P(S=0)

Answer 1

E(S)= 0

Anyone for SE(S) and P(S=0) ?

Answer 2

Thanks FLu!
Anyone for SE(S) and P(S=0)?

Answer 3

Thanks from me Flu

Answer 4

Thanks, anyone for the rest?

Answer 5

Could anyone tell me the SE(S)?

Answer 6

SE(E)- 4.472

Answer 7

Thanks Pebble.

Answer 8

Thanks Pebble, did someone solves or find the C....... P(S=0)?

Answer 9

1.0532687