Session 16: BODMAS (+,-, ×, ÷)
Session Title |
BODMAS (+,-, ×, ÷) |
Objectives |
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Topics |
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Materials required |
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Methodology |
The teacher explains BODMAS with examples. Students practice through group and individual work. |
Session Duration |
90 Minutes |
Introduction activity (1510 minutes):
Give the children problems first.
- 6 + 4 × 5 = ?
- (8 + 2) × (10 − 4) = ?
- 50 − 6 × 3 + 8 ÷ 2 = ?
- (36 ÷ 6) + 2 × (3 + 1) = ?
- 100 ÷ (5 × 2) + 3 = ?
- Then ask the students to find the answer.
- They will get different types of answers
- Then analyze why everyone gets different answers instead of the same ones.
- Then tell the children that we need to follow some rules to ensure that everyone gets the same correct answers
Then introduce BODMAS (3015 minutes)
BODMAS stands for Brackets, Orders, Division/Multiplication, Addition/Subtraction. It is a rule used to determine the order of operations when solving mathematical expressions. The steps are:
- Brackets: Solve anything inside parentheses first.
- Orders: Handle powers or roots (like squares, cubes, square roots, etc.).
- Division and Multiplication: From left to right.
- Addition and Subtraction: From left to right.
- This rule helps to avoid confusion and ensures everyone solves math problems the same way.
- Then ask them to redo the problem they tried to do first.
Practice session ( 4530 minutes )
Solve:
8+4×3-6÷2
Solution:
- According to BODMAS (Brackets, Orders (powers & roots), Division and Multiplication, Addition and Subtraction), we first handle multiplication and division from left to right, then addition and subtraction.
- Multiply and divide first: 8+(4×3)-(6÷2)=8+12-3
- Then, perform addition and subtraction from left to right:
8+12=20,20-3=17
Answer: 17
Solve
5×(6+4)-3square
Solution :
- Start with the parentheses : 5×(6+4)-3square =5×10-3 square
- Next, handle the exponent (3 squared): 5×10-9
- performe multiplication :50-9=41
Answer 41
Solve
(12÷4)+(5×2)-3
Solution :
1. Handle the division and multiplication first
(12÷4)+(5×2)-3=3+10-3
2. perform addition and subtraction:
3+10=13, 13-3=10
Answer 10
Game time (3020 minutes):
BODMAS Relay Race
Objective: Solve as many BODMAS problems as possible in a race format.
How to Play:
- Divide players into teams. Each team will have a whiteboard and a marker or paper and a pen.
- The host reads out a math problem that requires the BODMAS rule to solve (e.g., 3 × (4 + 2) - 5).
- The team must solve it step by step, following the BODMAS order.
- When the first team solves the problem correctly, they pass the turn to the next team member who has to solve a new problem.
- Continue until the team solves a set number of problems. The team that finishes first with all correct answers wins.
BODMAS Relay Race Problems
1. (4 + 6) × 3 - 8
- Step-by-step solution:
- First, solve inside the brackets: (4 + 6) = 10
- Then multiply: 10 × 3 = 30
- Finally subtract: 30 - 8 = 22
2. 8 × (5 + 7) ÷ 4
- Step-by-step solution:
- First, solve inside the brackets: (5 + 7) = 12
- Then multiply: 8 × 12 = 96
- Finally divide: 96 ÷ 4 = 24
3. (9 + 3) × 2 + 5
- Step-by-step solution:
- First, solve inside the brackets: (9 + 3) = 12
- Then multiply: 12 × 2 = 24
- Finally add: 24 + 5 = 29
4. (15 - 3) × (7 ÷ 7)
- Step-by-step solution:
- First, solve inside the brackets: (15 - 3) = 12 and (7 ÷ 7) = 1
- Then multiply: 12 × 1 = 12
- 5. (6 + 4) × (12 ÷ 3) - 2
Step-by-step solution:
- First, solve inside the brackets: (6 + 4) = 10 and (12 ÷ 3) = 4
- Then multiply: 10 × 4 = 40
- Finally subtract: 40 - 2 = 38
- 6. 5 × (8 ÷ 2) + (6 + 4)
- Step-by-step solution:
- First, solve inside the brackets: (8 ÷ 2) = 4 and (6 + 4) = 10
- Then multiply: 5 × 4 = 20
- Finally add: 20 + 10 = 30
7. (18 ÷ 3) + (6 × 2)
- Step-by-step solution:
- First, solve inside the brackets: (18 ÷ 3) = 6 and (6 × 2) = 12
- Then add: 6 + 12 = 18
8. (7 × 2) + (8 ÷ 4) - 5
- Step-by-step solution:
- First, solve inside the brackets: (7 × 2) = 14 and (8 ÷ 4) = 2
- Then add: 14 + 2 = 16
- Finally subtract: 16 - 5 = 11
9. (12 ÷ 2) × (9 - 4)
- Step-by-step solution:
- First, solve inside the brackets: (12 ÷ 2) = 6 and (9 - 4) = 5
- Then multiply: 6 × 5 = 30
10. (10 × 5) + (3 × 2) - 4
- Step-by-step solution:
- First, solve inside the brackets: (10 × 5) = 50 and (3 × 2) = 6
- Then add: 50 + 6 = 56
- Finally subtract: 56 - 4 = 52
Review Questions (5 minutes)
Why is the order of operations important in math?
What happens if we don’t follow BODMAS correctly?
Which part of BODMAS do you find most challenging and why?
How do brackets change the outcome of an expression?
Follow up task
1. BODMAS Warm-Up
Simplify the following using BODMAS:
a) 6 + 3 × 2
b) (4 + 5) × 3
c) 18 ÷ (3 × 3)
d) 24 – [6 + (2 × 3)]
Expected Learning Outcome
Skill Building
Recognition Skils.
Sequencing Skills
Computation Skills
Problem-Solving Skills
Explanation and Reasoning