Respuesta :
Answer:
Step-by-step explanation:
Given that a student takes a 20-question, multiple-choice exam with five choices for each question and guesses on each question.
Since each question has 5 choices p = probability for success = pr for getting correct guess = 0.2
Each question is independent of the other and q= pr for failure =1-0.2=0.8
Hence we have X, no of correct questions in the test is binomial n =20 and p =0.2
the probability of guessing at least 15 out of 20 correctly
= [tex]P(x=15)\\=20C15 (0.2)^{15} (0.8)^5[/tex]
<0.00001
So we can consider this event unlikely to occur because the probability is almost zero.
Probability is a measure of the likelihood of an event to occur. Many events cannot be predicted with total certainty.
The probability of unlikely to occur because the probability is almost zero.
Given
A student takes a 20-question, multiple-choice exam with five choices for each question and guesses on each question.
What is probability?
Probability is a measure of the likelihood of an event to occur. Many events cannot be predicted with total certainty.
The probability of getting each question has 5 choices is 0.2.
The probability of guessing at least 15 out of 20 correctly is determined by;
[tex]\rm P(x=15) = ^{20}c_{15}. (0.2)^{15}. (1-0.2)^5\\\\ P(x=15) = 0.327\times 0.00003 \times 0.32\\\\ P(x=15) = 0.00001[/tex]
Hence, The probability of unlikely to occur because the probability is almost zero.
To know more about Probability click the link given below.
https://brainly.com/question/2488960
