Calculating Percentiles

Test scores are normally distributed with a mean of 79 and a standard deviation of 3.1. Your test score was 76; what percentile does your test score represent?

• 76th Percentile

• 97th Percentile

• 17th Percentile

• 79th Percentile

Tags

CCSS.HSS.ID.A.4

Gas mileage for a group of company cars can be described by N (21, 2) in miles per gallon. The budget department is collecting data and attempting to find the gas mileage that represents the 85th percentile.

Which of the following equations is correct for finding the 85th percentile for this dataset?

• 2.33
• Unknown
• 46
• 4
• 2.58
• 1.72

Tags

CCSS.HSS.ID.A.4

Speeds on a highway are normally distributed with a mean of 82 miles per hour and a standard deviation of 7 miles per hour. What speed represents the 36th percentile?

• 36 MPH

• 80 MPH

• 79.5 MPH

• Not Enough Info

Tags

CCSS.HSS.ID.A.4

• 75th
• 0.67
• 16.1
• 50th
• 96.9

Tags

CCSS.6.SP.B.5C

Your teacher has asked you to use your calculator to find the value that represents the 18th percentile for a distribution that follows N(22, 6).

What mistake have you made?

• The tail should be centered

• The mean and standard deviation are incorrect

• The area should be 0.18

• No mistake has been made

Tags

CCSS.HSS.ID.A.4

A pharmaceutical company has a fleet of cars available to its representatives. In order to cut costs, the company wants to sell the cars that get the worst gas mileage. The gas mileage in their cars is normally distributed with a mean of 23.6 with a standard deviation of 0.4. They plan to only keep cars in the 10th percentile and greater.

Which of the following cars would the company NOT keep?

• Car 52 that gets 24 Mi/Gal

• Car 12 that gets 23 Mi/Gal

• Car 18 that gets 23.5 Mi/Gal

• They would keep all of these cars

Tags

CCSS.HSS.ID.A.4