Workshop: Discrete Random Variables

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

Tags

CCSS.HSS.MD.A.1

CCSS.HSS.MD.A.3

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the mean. Round to the nearest hundredth.

• 31.8

• 15.68

• 0.20

• 1.00

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the standard deviation. Round to the nearest hundredth.

• 35.76

• 268.1

• 16.3

• 1279.35

Tags

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.4

Given the probability model in the table below, what is the expected value of the random variable?
  X        50          20        5
P(X)     0.1         0.3      0.6

• 14
• 4.67
• 5
• 7.5

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

CCSS.HSS.MD.B.5

Find the mean (expected value) of the probability distribution.

• 85

• 83.2

• 87.1

• 84.4

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

A company states that 2% of its computers are returned for defects.  We take a sample of 100 computers to find the probability of 10 being defective.  Is this a binomial distribution?

• No because there is not a fixed number of trials.
• No because their are more than 2 outcomes.
• Yes since there are a fixed number of independent trials, outcomes in 2 categories, and the probability of defect is constant.
• No since computers would not be independent.

Tags

CCSS.HSS.CP.A.2

CCSS.HSS.CP.A.3

In a survey, 55% of the voters support a particular referendum. If 30 voters are chosen at random, find the standard deviation of the number of voters who support the referendum.

• 2.7

• 16.5

• 7.425

• 4.06

Tags

CCSS.HSS.ID.A.4

If 1.5% of the bolts made by an automotive factory are defective, what is the probability that in a shipment of 200 bolts, there are 6 defective bolts?

• 0.050

• 3

• 0.9676

• 0.09

Tags

CCSS.HSS.CP.B.9

CCSS.HSS.MD.A.3

A certain type of battery has a 0.5% failure rate. Find the probability that a shipment of 1,000 batteries has more than two defective batteries.

• 0.876

• 5

• 2.2304

• 0.9599

• The answer is not listed

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.3

If you were to flip a coin 20 times, what is the probability you would get exactly 10 heads?

• 50%
• 17.62%
• .58.81%
• 41.19%

Tags

CCSS.HSS.CP.B.9