FTCE GK Mathematics Mean Median Mode and Basic Probability Quiz

1. What is the mean of the data set: 8, 12, 15, 10, 20?

12

13

14

15

To find the mean, sum the numbers in the data set: 8 + 12 + 15 + 10 + 20 = 65. Then, divide the total by the number of values, which is 5. Therefore, 65 ÷ 5 = 13. Thus, the mean of the data set is 13.

Explanation

To find the mean, sum the numbers in the data set: 8 + 12 + 15 + 10 + 20 = 65. Then, divide the total by the number of values, which is 5. Therefore, 65 ÷ 5 = 13. Thus, the mean of the data set is 13.

2. Find the median of: 5, 9, 3, 7, 11, 2, 8.

7

8

6

9

To find the median, first arrange the numbers in ascending order: 2, 3, 5, 7, 8, 9, 11. Since there are seven numbers (an odd amount), the median is the middle number, which is the fourth number in this ordered list. Therefore, the median is 7.

Explanation

To find the median, first arrange the numbers in ascending order: 2, 3, 5, 7, 8, 9, 11. Since there are seven numbers (an odd amount), the median is the middle number, which is the fourth number in this ordered list. Therefore, the median is 7.

3. Identify the mode in this data set: 4, 7, 4, 9, 7, 4, 2.

2

4

7

9

The mode is the number that appears most frequently in a data set. In the given numbers, 4 appears three times, while the other numbers appear less frequently. Therefore, 4 is the mode of this data set, as it is the value that occurs most often.

Explanation

The mode is the number that appears most frequently in a data set. In the given numbers, 4 appears three times, while the other numbers appear less frequently. Therefore, 4 is the mode of this data set, as it is the value that occurs most often.

4. If a data set has values 10, 15, 20, 25, 30, what is the mean?

18

20

22

25

To find the mean, sum all the values: 10 + 15 + 20 + 25 + 30 = 100. Then, divide the total by the number of values, which is 5. Thus, 100 ÷ 5 = 20. This represents the average of the data set.

Explanation

To find the mean, sum all the values: 10 + 15 + 20 + 25 + 30 = 100. Then, divide the total by the number of values, which is 5. Thus, 100 ÷ 5 = 20. This represents the average of the data set.

5. What is the median of: 2, 5, 8, 12, 18?

5

8

9

10

To find the median, first arrange the numbers in ascending order: 2, 5, 8, 12, 18. The median is the middle value in a sorted list. Since there are five numbers, the third number (8) is the median, as it divides the dataset into two equal halves.

Explanation

To find the median, first arrange the numbers in ascending order: 2, 5, 8, 12, 18. The median is the middle value in a sorted list. Since there are five numbers, the third number (8) is the median, as it divides the dataset into two equal halves.

6. A data set contains: 3, 3, 5, 5, 5, 7, 9. Which is the mode?

3

5

7

9

The mode of a data set is the value that appears most frequently. In this case, the number 5 occurs three times, more than any other number in the set. Therefore, 5 is identified as the mode, as it has the highest frequency compared to the other values.

Explanation

The mode of a data set is the value that appears most frequently. In this case, the number 5 occurs three times, more than any other number in the set. Therefore, 5 is identified as the mode, as it has the highest frequency compared to the other values.

7. If you roll a fair six-sided die, what is the probability of rolling a 3?

1/6

1/3

1/2

2/3

When rolling a fair six-sided die, each face has an equal chance of landing face up. Since there is only one face with the number 3 and six total faces, the probability of rolling a 3 is 1 out of 6, or 1/6.

Explanation

When rolling a fair six-sided die, each face has an equal chance of landing face up. Since there is only one face with the number 3 and six total faces, the probability of rolling a 3 is 1 out of 6, or 1/6.

8. A bag contains 4 red, 3 blue, and 2 green marbles. What is the probability of drawing a red marble?

2/9

1/3

4/9

1/2

To find the probability of drawing a red marble, divide the number of red marbles by the total number of marbles. There are 4 red marbles and a total of 9 marbles (4 red + 3 blue + 2 green). Therefore, the probability is 4/9.

Explanation

To find the probability of drawing a red marble, divide the number of red marbles by the total number of marbles. There are 4 red marbles and a total of 9 marbles (4 red + 3 blue + 2 green). Therefore, the probability is 4/9.

9. Calculate the mean of: 25, 30, 35, 40, 45.

33

35

37

40

To find the mean, sum all the numbers: 25 + 30 + 35 + 40 + 45 = 175. Then, divide by the total count of numbers, which is 5: 175 ÷ 5 = 35. Thus, the mean of the given set is 35.

Explanation

To find the mean, sum all the numbers: 25 + 30 + 35 + 40 + 45 = 175. Then, divide by the total count of numbers, which is 5: 175 ÷ 5 = 35. Thus, the mean of the given set is 35.

10. If two fair coins are flipped, what is the probability of getting at least one heads?

1/4

1/2

2/3

3/4

When flipping two fair coins, the possible outcomes are HH, HT, TH, and TT, totaling four outcomes. Only one outcome (TT) does not have at least one heads. Therefore, the probability of getting at least one heads is 3 favorable outcomes (HH, HT, TH) out of 4 total outcomes, resulting in a probability of 3/4.

Explanation

When flipping two fair coins, the possible outcomes are HH, HT, TH, and TT, totaling four outcomes. Only one outcome (TT) does not have at least one heads. Therefore, the probability of getting at least one heads is 3 favorable outcomes (HH, HT, TH) out of 4 total outcomes, resulting in a probability of 3/4.

11. Find the median of: 14, 8, 22, 5, 18, 11, 25.

11

14

18

22

To find the median, first arrange the numbers in ascending order: 5, 8, 11, 14, 18, 22, 25. Since there are seven numbers (an odd count), the median is the middle value, which is the fourth number in this ordered list. Thus, the median is 14.

Explanation

To find the median, first arrange the numbers in ascending order: 5, 8, 11, 14, 18, 22, 25. Since there are seven numbers (an odd count), the median is the middle value, which is the fourth number in this ordered list. Thus, the median is 14.

12. In the data set 6, 6, 6, 9, 12, what is the mode?

6

9

12

No mode

The mode is the number that appears most frequently in a data set. In the given set (6, 6, 6, 9, 12), the number 6 appears three times, while the others appear less frequently. Therefore, 6 is the mode of this data set.

Explanation

The mode is the number that appears most frequently in a data set. In the given set (6, 6, 6, 9, 12), the number 6 appears three times, while the others appear less frequently. Therefore, 6 is the mode of this data set.