Question

In a multiple choice there are 20 questions. for each question there is a choice of four answers and only of of these is correct. Suppose 5 students guess answers to the test. What is the probability that at least two of them get more than ten answers correct?

Answer 1

@jim_thompson5910

Answer 2

how far did you get here?

Answer 3

@jim_thompson5910 I got nothing... ):

Answer 4

what are n and p in this case?

Answer 5

probability of correct = 0.25... is this p? and q=20? i have no idea. I only understand that the question seems to be asking for 2 different cases?

Answer 6

p = 0.25 (probability of success)
q = 1-p (probability of failure)
n = 20 (number of questions)

Answer 7

let me think for a sec

Answer 8

ok. so what about the introduction of the 5 students? @jim_thompson5910

Answer 9

"In a multiple choice there are 20 questions"

there are 5 students. So there are really 5*20 = 100 questions. Agreed?

Answer 10

huh.. alright...

Answer 11

@jim_thompson5910 please continue :)

Answer 12

sorry I'm thinking of a good way to word it

Answer 13

@jim_thompson5910 oh sorry please take your time :3

Answer 14

imagine you have 5 rows of boxes

each row represents a person

in each row you have 20 boxes (so you have 5*20 = 100 boxes total)

each box represents a question. You can place C for correct in it, N for not correct.



I couldnt' fit all the 20 boxes in the drawing, so I used the dots (...) to represent it