GCSE Statistics Normal Distribution

What percent of students have a height between 58 inches and 60 inches?

• 25%

• 50%

• 75%

• 100%

If a set of data has a Median of 23 and a Mean of 23, what type of skew would you expect to see?

• Negative Skew

• Normal Distribution

• Positive Skew

• Symmetrically Skewed

If a set of data has a Median of 50.56 and a Mean of 50.56, what type of skew would you expect to see?

• Symmetrically Skewed

• Normal Distribution

• Positive Skew

• Not enough information.

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days.

About what percent of the products last between 12 and 15 days?

• 68%

• 34%

• 16%

• 2.5%

What type of distribution is pictured?

• Right skewed

• Left skewed

• Random

• Normal

This data is normally distributed.  What percentage of the data is in the shaded region?

• 68%

• 34%

• 17%

• 50%

The green normal distribution curve has a standard deviation of 20. Does the purple normal distribution curve have a standard deviation that is larger or smaller than 20?​ (a)  

• larger

• smaller

A grading scale is set up for 1000 students' test scores. It is assumed the scores are normally distributed with a mean score of 75 and a standard deviation of 15. If a grade of a 60 is the lowest passing score, how many students are expected to pass the test? ​ (a)   How many students are expected to fail the test? ​ (b)  

• 840 students

• 160 students

• 84 students

• 16 students

• 877 students

• 123 students

The monthly income of 5000 workers at the Microsoft plant are distributed normally. Suppose the mean monthly income is $1250 and the standard deviation is $250.

Creating a normal distribution curve shows that the percentage of workers who earn between $750 and $1500 per month is ​ (a)  

• 800 workers

• 125 workers

• 81.5% of workers

• 97.5% of workers

​ The monthly income of 5000 workers at the Microsoft plant are distributed normally. Suppose the mean monthly income is $1250 and the standard deviation is $250.

Creating a normal distribution curve shows that the amount of workers who earn more than $1500 per month is ​ (a)  

• 800 workers

• 125 workers

• 81.5% of workers

• 97.5% of workers