a multiple choice exam is made up of 10 questions each question has 5 options and only one of them is correct if a person
Question
A multiple choice exam is made up of 10 questions; Each question has 5 options and only one of them is correct. If a person answers at random, what is the probability of answering only 3 good questions?
115
likes
574 views
Answer to a math question A multiple choice exam is made up of 10 questions; Each question has 5 options and only one of them is correct. If a person answers at random, what is the probability of answering only 3 good questions?
Fórmula de probabilidad binomial P(X=k)=(n,k)*p^k * (1-p)^(nk)
n=10 (10 preguntas)
k=3 (3 respuestas correctas)
p=1/5 (probabilidad de responder correctamente a una pregunta, ya que hay 5 opciones y solo una es correcta
P(X=3)=(10,3)*(1/5)^3 * (4/5)^7
P(X=3)= (10!/3!7!)(1/5)^3 * (4/5)^7 = 0,201
Entonces, la probabilidad de responder correctamente sólo 3 preguntas es aproximadamente 0,201, o 20,1%.
Frequently asked questions (FAQs)
Question: Find the value of arccos(-√2/2) - arcsin(-1/√2)
+
What is the value of 5 to the power of 2 multiplied by 3 to the power of 4, divided by 2 to the power of 3?
+
What is the area of a triangle with base 4 cm and height 6 cm?