S2/3-S1: Data Analysis

 DATA ANALYSIS 

Average = mean = Add all numbers/ how many numbers there are

Mode = the number/things that appears the most time.

Median = middle number in a ‘sorted list of values’

Example: 

Number list [ 2,3,9,3,6,2,3,4]

Average/Mean = 2+3+9+3+6+2+3+4 / 8 = 4

Arranged Number list [2,2,3,3,3,4,6,9]

Mode = 3 (appear the most number of times)

Median = (3 + 3) / 2 = 3 (for even list of number0

If arranged number list is [2,2,3,3,4,5,6,9,9]

        median = 4 [(Total number in list – 1) / 2]

From Frequency Table

            

Mean = (0x3) + (1x6) + (2x0) + (3x2) + (4x1) / (3+6+0+2+1)

Mode = 2 (has the highest frequency)

Median:

Total Frequency = 3+6+2+1 = 12

For even frequency, position of median number is 12/2 = 6 => Position is 6 and 7.

Median = 1

For odd frequency, position of median number is (total frequency -1)/2

S2-L25 Statistics Practice : Average

(Part 1) TEACHING(10-15mins)                

1.  Relationship between average, total value of data, word problems

(Part2) PRACTICE (20-35mins)
Find the average of:

1.   38, 41 and 44

2.   $130, $125, $108

3.   38kg, 37kg, 44kg, 41kg

4. The table shows the amount of money John saved from January to April.

What was the amount of money John saved in May if the average amount of money he saved from January to May is $32? (15/p1/18f)

(1) $25     

(2) $32     

(3) $64     

(4) $160                                                                                       (                       )

5.  The weight of Parcel A is 6 kg. Parcel B is as heavy as Parcel A. Parcel C is twice as heavy as Parcel B. What is the average mass of the 3 parcels?

6.  The average cost of 3 magazine is 8$. The total cost of 2 of the magazine is $6.8. What is the cost of the third card?

7.  The average mass of 5 boxes is 225g. What is the total mass of the 5 boxes?

8.   Remy spent an average of $3 per day from Monday to Friday. He spent an average of $5 per day for Saturday and Sunday. How much did he spend in one week? (23/p1/s18)

9.The average number of mangoes in 5 baskets was 53. Whenanother basket of mangoes was added, the average number of mangoes became 49. How many mangoes were there in the last basket? (/183/p2/s)

Extra Practice

1. *  The average of 9 numbers is 140. One of the numbers is 180. What is the average of the other 8 numbers?

2.  Amy scored an average of 80 marks for 3 tests. She scored 82 and 75 mars for the first two tests. What was her score for the third test?

3.*  Calvin bought some goldfish at $10 each. He also bought an equal number of angelfish at a different price. The average price of a goldfish and an anglefish was $7.

Calvin paid $54 more for the goldfish than the anglefish. How may goldfish did he buy?

4.  The pass of Parcel A is 6 kg. Parcel B is as heavy as Parcel A. Parcel C is twice as heavy as Parcel B. What is the average mass of the 3 parcels?

Answer Keys

1.            41

2.            121

3.            40 kg

4.            1

5.            8 kg

6.            $10.40

7.            1125 kg

8.            $25

9.            29

S3-L26 Statistics Practice : Pie Charts

(Part 1) TEACHING(10-15mins)                                     

1.  Reading and interpreting pie chart data

(Part2) PRACTICE (20-30mins)
For question 1 and 2.
A group of pupils was asked on their preference of the different types of CCA. The pie chart below represents their preference. (18/13/p2/f)

1.   What fraction of the pupils chose Clubs as their favourite type of CCA?
2.   75 pupils chose Uniformed Groups as their favourite type of CCA. How many pupils chose Dances as their favourite CCA?

For Question 3 - 6.
The pie chart shows how Mavis spends her weekly pocket money of $30.

                     

3.  What fraction of her pocket money does she save?

4.  What fraction of her pocket money does she spend on drinks?

5.  How much of her pocket money does she spend on food?

6.  How much of her pocket money does she save?

For question 7-10.
The following pie chart shows the types of fruits Jane sold on Sunday morning.

                         

7.  How many oranges did she sell?

8.  What type of fruits did she sell the most?

9.  How many more apples than oranges did she sell?

10.  How many fruits did she sell altogether?

For question 11 – 13.
The pie chart shows the attendance at a running event.

11.What percentage of the participants were adults and teenagers?
12.What percentage of the participants were children?
13.If there were 280 teenagers, how many adults were there?

14.    The pie chart represents the favourite animal of the pupils in Primary 6 Benevolence. There are as many fish as birds. How many pupils chose the terrapins as their favourite animal? (14/p1)

(1) 2

(2) 4

(3) 5

(4) 8                                                                                              (                       )

For question 15 – 16.
The pie chart shows the favourite sports of some children.          (21/p1)


15.   If 4/5 of the children who like soccer are boys, what fraction of the total number of children are boys who like soccer?

16.There are 15 boys who like soccer. How many children are there altogether?

For question 17 – 18.
The pie chart below shows the different types of biscuits sold at a supermarket. 

Half of the biscuits sold at the supermarket were butter cookies. The number of packets of wafer biscuits sold was 1/3 of the number of packets of butter cookies sold.

17.What fraction of the biscuits sold were oatmeal cookies?

18.1470 packets of butter cookies were sold. Find the total number of packets of wafer biscuits and oatmeal cookies sold. (18/p2/18/s)

Extra Practice

1.*  The pie chart shows how John spent the money he has. What fraction of the money did he spend on watch?

                   

2. *   The pie chart shows the favourite colours of a group of children. What percentage of the children choose Blue as their favourite colour?

                  

3.  The pie chart shows the attendance at a running event

                     

(a)  What percentage of the participants were adults and teenagers?

(b)  What percentage of the participants were children?

(c)  If there were 280 teenagers, how many adults were there?

Answer Keys

1.            3/25

2.            63

3.            ½

4.            1/6

5.            $10

6.            $15

7.            15

8.            Apples

9.            3

10.         60

11.         83%

12.         17%

13.         384

14.         4

15.         3/5

16.         25

17.         1/6

18.         635