Mathematics, 06.05.2021 14:00 mchillery1028
There are 20 questions in a multiple choice exam, each with 4 answers and only one is correct. The students are guessing the answers in an independent way. Correct answer = +5, incorrect answer = -1, unaswered = 0.
What is the expected value of the grades, what is the variance of the grades and what is the probabilty to get the same grade as the expected value?
The answers are: 10, 135, 0.2.
I tried binomic distrubiton: p = 0.125 (0.5 if the students choose to answer the question and 0.25 if they're right) but I don't get the correct answers.
Thank you.
Answers: 3
Mathematics, 21.06.2019 20:00, alisonlebron15
An investment decreases in value by 30% in the first year and decreases by 40% in the second year. what is the percent decrease in percentage in the investment after two years
Answers: 1
Mathematics, 21.06.2019 23:00, serenityburke
The areas of two similar triangles are 72dm2 and 50dm2. the sum of their perimeters is 226dm. what is the perimeter of each of these triangles?
Answers: 1
Mathematics, 21.06.2019 23:20, ruddymorales1123
Identify the function that contains the data in the following table: x -2 0 2 3 5 f(x) 5 3 1 2 4 possible answers: f(x) = |x| + 1 f(x) = |x - 2| f(x) = |x - 2| - 1 f(x) = |x - 2| + 1
Answers: 1
There are 20 questions in a multiple choice exam, each with 4 answers and only one is correct. The s...
Mathematics, 21.02.2022 08:20
Mathematics, 21.02.2022 08:20
English, 21.02.2022 08:20
Mathematics, 21.02.2022 08:30