Random Variables

State whether it is Discrete or Continuous;

A film critic's rating of a film, 0 to 4 stars

• Discrete

• Continuous

State whether it is Discrete or Continuous;

The speed of a car

• Discrete

• Continuous

State whether it is Discrete or Continuous;

The sum rolled on a pair of dice

• Discrete

• Continuous

State whether it is Discrete or Continuous;

the amount of water in different types of fruit drink

• Discrete

• Continuous

The table above shows the number of cell phones per household in a small town. Find the mean round to the nearest hundredth.

• 2.80

• 2.93

• 0.10

• 0.14

A stockbroker estimates that at the end of the year, there is a 40% chance a stock will be worth $50, a 35% chance it will be worth $60 and a 25% chance it will be worth $70.
What expected value does this broker assign to this stock's end-of-the-year price?

• $58.50
• $60.00
• $62.50
• $65.00

In a certain community, 30% of households have 1 child, 43% have 2 children, and 27% have 3 children. If a household is selected at random, what is the expected number of children in that household? HINT: A Probability table may be helpful.

• 2.00
• 2.13
• 1.97
• 1.27

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

• 1.67

• 1.0775

• 1.581

• 1.414

The model shown above shows the probability for rental units based on the number of rooms. What is the expected value and the standard deviation of the number of rooms in a rental unit?

• 5, 2.7386

• 5, 2.5820

• 4.355, 1.5647

• 4.355, 1.2996