Scroll:Data Analysis >> Average of a Set of Data >> ps (1544)

Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.


 

1)  

The average number of sweets 3 children have is 15 
When 1 more child joins the group, the average number of sweets they have becomes 20.
What is the number of sweets the last child have


Answer:_______________




2)  

The average height of 3 boys is 1.72m.
One more boy whose height is 1.56m joins the group.
What is the average height of the 4 boys

___m


Answer:_______________




3)  

The average mass of 5 girls is 35kg 
When 2 more girls join the group, the average becomes 46kg.
What is the total mass of the 2 girls

kg


Answer:_______________




4)  

The average number of sweets 4 children have is 4.
When 2 more children join the group, the average number of sweets they have becomes 24.
What is the total number of sweets the last 2 children have altogether


Answer:_______________




5)  

There are 40 students in a class. The average score for a Science Test is 51 marks. After 2 students left the class, the average score for the test becomes 50 marks.

What are the total marks of the 2 students who left


Answer:_______________




6)  

The average number of sweets 3 children have is 18 
When 1 more child joins the group, the average number of sweets they have becomes 25.
What is the number of sweets the last child have


Answer:_______________




7)  

The average height of 3 boys is 1.60m.
One more boy whose height is 1.52m joins the group.
What is the average height of the 4 boys

___m


Answer:_______________




8)  

The average mass of 5 girls is 35kg 
When 2 more girls join the group, the average becomes 48kg.
What is the total mass of the 2 girls

kg


Answer:_______________




9)  

The average number of sweets 4 children have is 8.
When 2 more children join the group, the average number of sweets they have becomes 30.
What is the total number of sweets the last 2 children have altogether


Answer:_______________




10)  

There are 40 students in a class. The average score for a Science Test is 70 marks. After 2 students left the class, the average score for the test becomes 69 marks.

What are the total marks of the 2 students who left


Answer:_______________




 

1)  

The average number of sweets 3 children have is 15 
When 1 more child joins the group, the average number of sweets they have becomes 20.
What is the number of sweets the last child have

Answer: 35


SOLUTION 1 :

Step 1: 15 x 3 = 45

Step 2: 20 x 4 = 80

Step 3: 80 - 45 = 35



2)  

The average height of 3 boys is 1.72m.
One more boy whose height is 1.56m joins the group.
What is the average height of the 4 boys

Answer: 1.68m


SOLUTION 1 :

Step 1: Total height for the 3 boys : 1.72 x 3 = 5.16m

Step 2: Total height for the 4 boys : 5.16  + 1.56 = 6.72m

Step 3: Average height of the 4 boys : 6.72 ÷ 4 = 1.68m



3)  

The average mass of 5 girls is 35kg 
When 2 more girls join the group, the average becomes 46kg.
What is the total mass of the 2 girls

Answer: 147kg


SOLUTION 1 :

Step 1: 35 x 5 = 175kg

Step 2: 46 x 7 = 322kg

Step 3: 322 - 175 = 147kg



4)  

The average number of sweets 4 children have is 4.
When 2 more children join the group, the average number of sweets they have becomes 24.
What is the total number of sweets the last 2 children have altogether

Answer: 128


SOLUTION 1 :

Step 1: 4 x 4 = 16

Step 2: 24 x 6 = 144

Step 3: 144 - 16 = 128



5)  

There are 40 students in a class. The average score for a Science Test is 51 marks. After 2 students left the class, the average score for the test becomes 50 marks.

What are the total marks of the 2 students who left

Answer: 140


SOLUTION 1 :

Step 1: 51 x 40 = 2040

Step 2: 40 - 2 = 38

Step 3: 50 x 38 = 1900

Step 4: 2040 - 1900 = 140



6)  

The average number of sweets 3 children have is 18 
When 1 more child joins the group, the average number of sweets they have becomes 25.
What is the number of sweets the last child have

Answer: 46


SOLUTION 1 :

Step 1: 18 x 3 = 54

Step 2: 25 x 4 = 100

Step 3: 100 - 54 = 46



7)  

The average height of 3 boys is 1.60m.
One more boy whose height is 1.52m joins the group.
What is the average height of the 4 boys

Answer: 1.58m


SOLUTION 1 :

Step 1: Total height for the 3 boys : 1.60 x 3 = 4.8m

Step 2: Total height for the 4 boys : 4.8  + 1.52 = 6.32m

Step 3: Average height of the 4 boys : 6.32 ÷ 4 = 1.58m



8)  

The average mass of 5 girls is 35kg 
When 2 more girls join the group, the average becomes 48kg.
What is the total mass of the 2 girls

Answer: 161kg


SOLUTION 1 :

Step 1: 35 x 5 = 175kg

Step 2: 48 x 7 = 336kg

Step 3: 336 - 175 = 161kg



9)  

The average number of sweets 4 children have is 8.
When 2 more children join the group, the average number of sweets they have becomes 30.
What is the total number of sweets the last 2 children have altogether

Answer: 148


SOLUTION 1 :

Step 1: 8 x 4 = 32

Step 2: 30 x 6 = 180

Step 3: 180 - 32 = 148



10)  

There are 40 students in a class. The average score for a Science Test is 70 marks. After 2 students left the class, the average score for the test becomes 69 marks.

What are the total marks of the 2 students who left

Answer: 178


SOLUTION 1 :

Step 1: 70 x 40 = 2800

Step 2: 40 - 2 = 38

Step 3: 69 x 38 = 2622

Step 4: 2800 - 2622 = 178