Year 8 Maths: BIDMAS

What is BIDMAS?

BIDMAS is an acronym that helps you remember the order of operations in mathematics. This order is important when solving math problems that have more than one operation, like addition, subtraction, multiplication, and division.

BIDMAS stands for:

• Brackets
• Indices (or powers)
• Division
• Multiplication
• Addition
• Subtraction

This means you do calculations in the following order:

1. Brackets: Solve anything inside brackets first.
2. Indices: Next, calculate any powers or roots.
3. Division and Multiplication: Work from left to right.
4. Addition and Subtraction: Finally, work from left to right.

Let’s break it down further!

Step-by-Step Explanation

1. Brackets

Always solve what’s inside brackets first.

Example:

$$3 + (4 × 2)$$

First, calculate $$4 × 2 = 8$$ , then add:

$$3 + 8 = 11$$ .

2. Indices

Next, solve any indices (or powers).

Example:

$$2^3 + 4$$

First, calculate $$2^3 = 8$$ , then add:

$$8 + 4 = 12$$ .

3. Division and Multiplication

These operations are equal in priority, so do them from left to right.

Example:

$$18 ÷ 2 × 3$$

First, do $$18 ÷ 2 = 9$$ , then multiply:

$$9 × 3 = 27$$ .

4. Addition and Subtraction

Like division and multiplication, addition and subtraction are equal in priority. Again, do them from left to right.

Example:

$$10 – 3 + 2$$

First, do $$10 – 3 = 7$$ , then add:

$$7 + 2 = 9$$ .

Tips and Tricks

• Remember BIDMAS: Keep the acronym in mind to help you remember the order of operations.
• Work Slowly: Take your time to ensure you follow the order correctly.
• Double-Check Your Work: After solving, go back through the steps to check for any mistakes.

Practice Questions

Easy Level Questions (1-20)

1. $$2 + 3 × 4$$
2. $$(5 + 5) ÷ 2$$
3. $$6 × (2 + 1)$$
4. $$7 – 3 + 2$$
5. $$4 × 3 ÷ 2$$
6. $$(1 + 2) × 3$$
7. $$5^2 – 3$$
8. $$8 ÷ 4 + 2$$
9. $$(10 – 2) × 2$$
10. $$3 + 4 × 2 – 1$$
11. $$9 + (2 × 5)$$
12. $$15 ÷ (3 + 2)$$
13. $$(6 + 4) ÷ 2 + 1$$
14. $$2 × 2 + 4$$
15. $$5 + 5 – 10$$
16. $$12 ÷ 4 × 3$$
17. $$(8 – 3) + 2 × 2$$
18. $$10 – (3 + 2)$$
19. $$4 + 4 × 4$$
20. $$3^2 + 1$$

Medium Level Questions (21-40)

21. $$3 + 5 × (2 + 3)$$
22. $$(10 – 2) ÷ 2 + 3$$
23. $$4 × (3 + 2) – 1$$
24. $$8 – 3 + 4 ÷ 2$$
25. $$7 + 2^3 – 8$$
26. $$(5 × 5) ÷ 5 + 3$$
27. $$10 – 3 × (2 + 1)$$
28. $$6 + 4 × 2 – 5$$
29. $$(2 + 3)^2 – 5$$
30. $$12 ÷ 3 + 4 × 2$$
31. $$5^2 + (1 + 1) × 2$$
32. $$(9 – 3) × 2 + 1$$
33. $$3 × (4 + 5) – 6$$
34. $$10 ÷ (2 + 1) + 3$$
35. $$6 × 2 – (3 + 1)$$
36. $$2 + 2 × 2^2$$
37. $$(4 + 4) ÷ 2 + 5$$
38. $$7 + 10 ÷ (2 + 3)$$
39. $$1 + 2 × (3 + 4)$$
40. $$8 – 4^2 ÷ 2$$

Hard Level Questions (41-60)

41. $$5 × (3 + 1^2) – 7$$
42. $$(12 ÷ 4) + 3 × (1 + 2)$$
43. $$2 × (3 + 5) – (4 – 2)$$
44. $$6 + (2^2 × 3) – 4$$
45. $$5 + (10 – 3) × 2$$
46. $$8 – 6 + 3^2 ÷ 3$$
47. $$15 – (3 × (2 + 1)) + 10$$
48. $$20 ÷ (2 × 2) + 5$$
49. $$(4 × 5) – (6 ÷ 2) + 3$$
50. $$2^3 + (5 – 2) × 4$$
51. $$3 × (2 + 4) – (5 ÷ 5)$$
52. $$(8 – 3)^2 ÷ 5 + 2$$
53. $$10 + (4 ÷ 2) × 3 – 1$$
54. $$18 ÷ 3 + 2 × (3 + 1)$$
55. $$6 + (2^2 × 2) – 5$$
56. $$(10 – 4) × 3 – 2^2$$
57. $$12 ÷ (3 + 1) + 5 × 2$$
58. $$14 – (6 ÷ 2 + 4)$$
59. $$(5 + 5) ÷ 2 + 3^2$$
60. $$3 + 4 × (2^2 – 1)$$

Answers and Explanations

Easy Level Answers

1. 14
2. 5
3. 18
4. 6
5. 6
6. 9
7. 22
8. 4
9. 16
10. 10
11. 19
12. 3
13. 6
14. 8
15. 0
16. 9
17. 7
18. 5
19. 20
20. 10

Medium Level Answers

21. 28
22. 5
23. 19
24. 6
25. 1
26. 8
27. 1
28. 10
29. 20
30. 10
31. 8
32. 15
33. 21
34. 7
35. 2
36. 10
37. 8
38. 3
39. 15
40. 2

**Hard