(a) Find the probability that a randomly selected toothbrush (of this type) has a lifespan of more than 2 years. (b) Assume that a toothbrush of the same type has been working for one year already. What is the probability that it works for at least another 3 years?

A First Course in Probability (10th Edition)
10th Edition
ISBN:9780134753119
Author:Sheldon Ross
Publisher:Sheldon Ross
Chapter1: Combinatorial Analysis
Section: Chapter Questions
Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...
icon
Related questions
Question

(a) Find the probability that a randomly selected toothbrush (of this type) has a lifespan of
more than 2 years.

(b) Assume that a toothbrush of the same type has been working for one year already. What is the probability that it works for at least another 3 years?

 

The lifetime T (in years) for a particular type of electric toothbrush is assumed to have the
probability density f given by
t
f(t) =
0 ≤ t ≤6
-G
18
otherwise.
Transcribed Image Text:The lifetime T (in years) for a particular type of electric toothbrush is assumed to have the probability density f given by t f(t) = 0 ≤ t ≤6 -G 18 otherwise.
Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Recommended textbooks for you
A First Course in Probability (10th Edition)
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
A First Course in Probability
A First Course in Probability
Probability
ISBN:
9780321794772
Author:
Sheldon Ross
Publisher:
PEARSON