# Open Sentences

Subject : Mathematics

Class :Primary 6

Topic : Open Sentences

Term :Third Term

Week :Week 2

Previous Knowledge : Revision

Instructional Materials : Mathematics textbook, online materials, Wall charts

Behavioural Objectives : At the end of the lesson, pupils should be able to

Solve simple questions on open sentences

They should also be able to invert the addition ➕ sign to subtraction ➖ sign when moving figures over the equal to signs

They should also be able to change the division ➗ sign to multiplication ✖ sign when moving figures over the equal to sign

Content :

Open sentences are used in mathematics to hide the values of some certain numbers so that we can work out the values of such numbers

The unknown values in open sentences may be represented by any letters of the alphabet or shapes

If we want to determine the value of any unknown figures in open sentences, then we either do addition ➕, subtraction ➖. multiplication ✖, or division ➗ of numbers as the case may be to.

Samples :

Question 1. Given that b + 6 = 10

What is the value of b

Solution

b = 10.- 6

b=4

Ans = 4

Question 2. 4x= 24, what is the value of x

Solution

Given that 4x=24

X=24/4

X=6

Ans =6

Question 3. If 40 notes are to be shared among 5 pupils, how many notebooks will be given to a pupil

Solution

5P= 40

P= 40 /5

P=8

Ans = 8 notes will be given to each pupil

Question 4

Given that 4x+2 =6+2x

What is the value of x

Solution

Collect like Term

4x-2x=6-2

2x=4

Divide both sides by 2

2x/2 = 4/2

X = 2

Presentation

Step 1

The teacher revises the previous topics

Step 2

The teacher introduces the new topic

Step 3

The teacher allows the pupils to give their own contributions and he allows them to feel free

Evaluation

Class work

Question 1.

b+ 20 = 16

What is the value of b

Question 2.

If 60 apples are to be shared among 6 boys, how many apples will each boy collect

Question 3

4q + 10q = 350

What is the value of q

Question 4

9y+24=4y – 16

What is the value of y

Conclusion :

The class teacher does the necessary corrections and he goes round to mark