EBook Problems Distrib RV

From Socr

Revision as of 23:32, 28 December 2008 by JayZzz (Talk | contribs)
(diff) ← Older revision | Current revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Contents

EBook Problems Set - Random Variables

Problem 1

The probability model below describes the number of repair calls that an appliance repair shop may receive during an hour:

Repair calls 0 1 2 3
P(x) 0.1 0.3 0.4 0.2

The probability that the number of repair calls is at least 2 is:

  • Choose one answer.
(a) 0.8
(b) 0.2
(c) 0.4
(d) 0.6


Problem 2

In a litter of seven kittens, three are female. You pick two kittens at random. The probability model for the number of male kittens is:

Number males 0 1 2
Probability 0.143 0.571 0.286

The expected number of males is:

  • Choose one answer.
(a) 0.64
(b) 1.7
(c) 1.14
(d) 2.1


Problem 3

Let X represent a discrete random variable that takes any of the values and probabilities given below:

X -2 5 6
P(X) 0.4 0.4 __

The probability for X = 6 is missing. What is it?

  • Choose one answer.
(a) It cannot be determined from the information given
(b) 0.2
(c) 0.6
(d) 2.3


Problem 4

The manager of a stock room in a factory knows from her study of records that the daily demand for a certain tool has the following probability model:

Demand 0 1 2
Probability 0.1 0.5 0.4

Suppose it costs the factory $10 each time the tool is used. Find the variance of the daily cost of using the tool.

  • Choose one answer.
(a) 13
(b) 41
(c) 1.3
(d) 10





Translate this page:

(default)

Deutsch

Español

Français

Italiano

Português

日本語

България

الامارات العربية المتحدة

Suomi

इस भाषा में

Norge

한국어

中文

繁体中文

Русский

Nederlands

Ελληνικά

Hrvatska

Česká republika

Danmark

Polska

România

Sverige

Personal tools