Mr. Emil Grade 12 Term 3 First Quiz

Ahmed sells items from a catalog to raise money for school. He has a 32% chance of making a sale each time he solicits a potential customer. Ahmed asks 15 people to purchase an item. Find the probability that exactly 5 people make a purchase.

In a recent poll, 45% of teenagers said they exercise regularly. Seven teenagers chosen at random are asked if they exercise regularly. Find the value of the mean

Use the following probability distribution to find the expected value (the mean) ,E(x)

Determine which of the following survey questions is unbiased.

• Would you like our product to be cheaper and more value for money?

• How likely are you to recommend working with our current agency?

• Do you prefer watching exciting action movies or boring documentaries?

• How often do you go to the cinema?

Find the inter-quartile Range (IQR) for the following data:

20 ,23, 18, 12 , 38 ,16 , 29 , 21 , 30 , 27, 42

Determine which of the following represents an observational study.

• The city council wants to start a recycling Program. They sent a questionnaire to 200 random citizens asking what items they would recycle.

• A record label wants to test three designs for an album cover. They randomly selected 50 teenagers from local high schools to view the covers while they watched and recorded their reactions.

• A pharmaceutical company wants to test whether a new medicine is effective.

• A news organization wants to call citizens to gauge presidential election opinions randomly.

If the variance of a probability distribution equals 9, then find the standard deviation

Use the following probability distribution to find the value of (k).

The weights of 1200 bodybuilders are normally distributed with a mean of 74 kg, and a standard deviation of 4.5kg. Find the number of bodybuilders that have weight greater than 82 kg.