# Worksheet: The Mean of a Data Set

In this worksheet, we will practice calculating the mean of a set of whole numbers or decimals.

Q1:

Which of the following data sets has a mean of 59?

• A52, 76, 23, 50, 15
• B81, 34, 85, 21, 76
• C74, 79, 27, 59, 56
• D90, 64, 49, 13, 50
• E11, 50, 21, 72, 48

Q2:

In order to get a C in math, James must have an average score of 70 or more. His test scores so far are 63.3, 85, 79.73, and 70.57. Calculate the minimum score James needs to get on his final test to earn a C.

Q3:

The table shows the number of subscribers of several internet providers. What is the mean number of subscribers for these internet providers?

 Internet Provider Subscribers (millions) Company A Company B Company C 1.65 1.16 1.9
• A1 million
• B1.07 million
• C2.35 million
• D2.07 million
• E1.57 million

Q4:

Find, to two decimal places, the mean of the test scores in the table. Then determine which group’s score is closest to the mean.

 Class Group Test Score Group A Group B Group C Group D Group E Group F Group G Group H 78 86 72 93 92 84 87 70
• AThe mean is 84.57, and Group F is the closest to the mean.
• BThe mean is 94.57, and Group D is the closest to the mean.
• CThe mean is 82.75, and Group G is the closest to the mean.
• DThe mean is 82.75, and Group F is the closest to the mean.
• EThe mean is 82.75, and Group E is the closest to the mean.

Q5:

Find the mean of the following set of data: 9.2, 2.5, 1.7, 2.2, 6.4, 9.1, 2.2, 5.9. If necessary, round your answer to the nearest tenth.

Q6:

Daniel has the following data: 18, , 11, 15.

If the mean is 13, find the value of .

Q7:

What is the mean of the following numbers: 6, 4, 5, 3, 5, 1?

Q8:

Given that the mean of the side lengths of a triangle is 150 cm, determine its perimeter.

Q9:

Calculate the mean of the values in the table.

 17 25 13 22 15 17 24 21 23 14 19 22 19 16 18

Q10:

Find the mean of the values 15, 20, 37, 43, 13, 34, 41, and 39.

Q11:

Given that the mean of the values is 11, find the value of .

Q12:

Calculate the mean of the values given in the table.

 136 136 139 135 117 135 120 125 116 131

Q13:

Find the mean of the following set of data: 5.53, 7.74, 8.91, 4.31, 3.22.

Q14:

Determine the mean of three numbers which sum to 42.

Q15:

Find, to the nearest cent, the mean of the set of costs in the table.

CostTallyFrequency
\$12.6411
\$18.0615
\$10.5010

Q16:

Find the mean of the set of data in the line plot. If necessary, write your answer to the nearest tenth. Q17:

Before the last soccer game of the season, David scored a total of 23 goals. He scored 5 goals in the final game, with an average of 4 goals per game this season. To calculate the total number of games David played, we first find the sum of 23 and 5. What would be the next step?

• Adivide the sum by 5
• Badd the sum to 4
• Cmultiply the sum by 4
• Dsubtract 4 from 230
• Edivide the sum by 4

Q18:

Given the mean of the values 8, 22, 4, 12, and is 15, find the value of .

Q19:

A student’s mean score in four tests is 35 marks. After he takes a fifth test, his mean score increases to 37 marks. What was his score on the fifth test?

Q20:

The table shows the total precipitation in Arches National Park in January of each year. Calculate the mean January precipitation over the entire period shown in the table.

 Year Precipitation (in) 1,997 1,998 1,999 2,000 2,001 2,002 2,003 2,004 1.09 0.013 0.54 0.80 0.89 0.24 0.11 0.16

Q21:

The mean of the given data set is 7. Find the missing value .

 9 6 3 8 5 𝑥

Q22:

Given that the mean of the marks of 9 students is 45, determine the sum of their marks.

Q23:

A student takes five tests: A, B, C, D, and E. Their mean score for tests A, B, and C is 48. Their mean score for tests D and E is 38. Calculate the mean score of all 5 tests.

Q24:

The table shows how much Jacob saved each day. Describe how the mean would be affected if the savings for Monday were not included.

 Day Amount Saved Saturday Sunday Monday Tuesday Wednesday Thursday \$11.90 \$6.00 \$3.70 \$3.10 \$6.10 \$8.10
• AThe mean would decrease from \$11.90 to \$6.48.
• BThe mean would increase from \$6.48 to \$11.90.
• CThe mean would increase from \$6.48 to \$7.04.
• DThe mean would remain unchaged at \$6.48.
• EThe mean would decrease from \$7.04 to \$6.48.

Q25:

If the mean age of two people is 50 and one of the people is 54 years old, how old is the other person?