1.4 Quiz B (Percents and Percentiles)

First Name

Last Name

Period

1) What is the percentile for a z-score of z = -0.83?

• 15th
• 20th
• 24th
• 31st

2) Adrian’s average bowling score is 174, and is normally distributed with a standard deviation of 35. In what percent of games does Adrian score more than 200 points?

• 56.32%
• 29.07%
• 22.88%
• 14.39%

3) The top 10% of bowlers in Adrian’s league get to play in an all-star game. If the league average is 170, with a standard deviation of 11 points, and is normally distributed what average score does Adrian need to have to obtain a spot in the all-star game? (round to the nearest whole score)

4) IQ score of people around the world are normally distributed, with a mean of 100 and a standard deviation of 15. A genius is someone with an IQ greater than or equal to 140. What percent of the population is considered genius?

• 38% of the population
• 3.8% of the population
• 0.38% of the population

5) A standardized test is known to be normally distributed with a mean of 500 and a standard deviation of 110. A student’s score is 675, what percentile is she in?

• the 75th percentile
• the 94th percentile
• the 6th percentile
• the 28th percentile

6) Another student taking the same test wants to score in the 80th percentile. What score must he get?

• 592.6
• 588.1
• 573.2
• 507.5

7) How many planes have a mass less than 4 kg?

• About 8 planes
• About 9 planes
• About 11 planes
• About 12 planes