Biology Forums - Study Force

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons, and it is assumed that the amount of gasoline purchased per car is symmetric, there is approximately a 68.26 chance that a random sample of 16 cars will have a sample mean between 14 and 16 gallons.
 
  Indicate whether the statement is true or false

Q. 2

If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will take between 2 and 4.5 minutes to find a parking spot in the library parking lot.
 
  A) 0.4938 B) 0.0919 C) 0.2255 D) 0.7745

Q. 3

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons, and a random sample of 4 cars is selected, there is approximately a 68.26 chance that the sample mean will be between 13 and 17 gallons.
 
  Indicate whether the statement is true or false

Q. 4

If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will find a parking spot in the library parking lot in less than 3 minutes.
 
  A) 0.3085 B) 0.1915 C) 0.3551 D) 0.2674

Ans. #1

TRUE

Ans. #2

D

Ans. #3

FALSE

Ans. #4

A

Passed my quiz with this!