# Prioritise Operations using BIDMAS

In this worksheet, students will replace letters with numbers and solve problems using BIDMAS. They must give their final answers as letters not numbers.

Key stage:  KS 2

Curriculum topic:   Verbal Reasoning

Curriculum subtopic:   Maths Codes

Difficulty level:

### QUESTION 1 of 10

Make sure that you’ve got your thinking cap on as we are going to be number decoders!

For this activity, we must follow the rules of BIDMAS (or you may know them as BODMAS).

BIDMAS tells us the order in which we should answer long calculations:

 1 B Brackets Anything inside brackets must be calculated first. 2 I Indices (or Orders) Any square numbers or square roots must be calculated next. 3 D  M Division and Multiplication Then division and multiplication. If you have both of these in the same calculation, then complete it from left to right as it has been written. 4 A  S Addition and Subtraction Then addition and subtraction. Again, if you have both of these in the same calculation, then complete it from left to right as it has been written.

Let’s crack a code using BIDMAS:

If a = 8, b = 6, c = 3, d = 7 and e = 12, what is b x a ÷ e + c?

First, we must swap the letters back into numbers to help us work it out. This would be written as: 6 x 8 ÷ 12 + 3= ___.

There are not any brackets or indices so, according to BIDMAS rules, we must calculate the multiplication and division first. This must be done in the order that it is written, so 6 x 8 = 48.

Then we are left with: 48 ÷ 12 + 3.

Following BIDMAS, let’s do the division first, 48 ÷ 12 = 4.

Then we are left with 4 + 3 = 7.

So the answer is 7 but we must convert this back into a letter. The number 7 is represented by the letter d, therefore d is the final answer.

Let’s try one more and write the answer as a letter:

If a = 4, b = 125 , c = 3, d = 11 and e = 7, what is d (c x a) - e?

Where there isn’t a -, +, x or ÷ between the first letter and the bracket, it means we have to multiply the outside number by what is in the brackets.

So the steps we follow are:

c x a = 12

d x 12 = 132

132 - e = 125

We must turn the number 125 back into a letter. This number corresponds to the letter b.

Now it’s your turn to crack the codes. Good luck number detective!

Match up the letters from BIDMAS to their meanings.

## Column B

B
Indices or orders (such as squared numbers or squa...
I
Multiplication
D
Division
M
Brackets
A
Subtraction
S

When you see division and multiplication in a calculation, what should you do according to the rules of BIDMAS

You must divide first

You must multiply first

If they are both present, you complete from left to right

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

B x A ÷ E - C

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

B (A ÷ E) - C

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

c + d x e

If C = 7, D = 15 and E = 2, what is C + D x E?

37

44

29

If c = 7, d = 15 and e = 2, what is (c + d) ÷ e?

12

22

11

If c = 7, d = 15 and e = 2, what is c + d - e?

12

20

11

When you see addition and subtraction in a calculation, what should you do according to the rules of BIDMAS

You must subtract first

If both are present, you complete them from left to right

If a = 32, b = 2, c = 7, d = 15 and e = 4, what is b (a ÷ e) - c?

10

9

11

• Question 1

Match up the letters from BIDMAS to their meanings.

## Column B

B
Brackets
I
Indices or orders (such as square...
D
Division
M
Multiplication
A
S
Subtraction
EDDIE SAYS
BIDMAS stands for Brackets, Indices (or Orders), Division and Multiplication, Addition and Subtraction.
The word BIDMAS uses the first letter from each description in order so it is easy to remember.
BIDMAS is important as it tells us the order in which to prioritise operations in calculations.
• Question 2

When you see division and multiplication in a calculation, what should you do according to the rules of BIDMAS

If they are both present, you complete from left to right
EDDIE SAYS
In BIDMAS, multiplication and division are given equal weight in terms of priorities.
So if both division and multiplication appear in the same question, then you calculate steps from the left to right.
• Question 3

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

B x A ÷ E - C
EDDIE SAYS
There are three operations present in this calculation: x, ÷ and -.
According to the rules of BIDMAS, the subtraction (-) is the lowest priority.
The multiplication (x) and division (÷) have equal weight, so we should work through them in the order they have been written from left to right.
Using this information, the sum you should tackle first in this example is B x A.
• Question 4

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

B (A ÷ E) - C
EDDIE SAYS
There are three operations present in this calculation: brackets, ÷ and -.
According to the rules of BIDMAS, the subtraction (-) is the lowest priority.
The sum in brackets is the highest priority and needs to be tackled first.
The division (÷) has higher priority than the subtraction, but lower than the brackets, so should be tackled second.
Using this information, the sum you should tackle first in this example is B ÷ A.
• Question 5

According to the rules of BIDMAS, which part of the equation below would you would need to tackle first?

You should highlight the operation (+, -, x or ÷) and the two letters it affects to be marked correctly.

c + d x e
EDDIE SAYS
There are two operations present in this calculation: + and x.
According to the rules of BIDMAS, the addition (+) is the lowest priority.
The multiplication (x) is the highest priority and needs to be tackled first.
Using this information, the sum you should tackle first in this example is d x e.
• Question 6

If C = 7, D = 15 and E = 2, what is C + D x E?

37
EDDIE SAYS
There are two operations present in this calculation: + and x.
According to the rules of BIDMAS, the addition (+) is the lowest priority.
The multiplication (x) is the highest priority and needs to be tackled first.
Working out the multiplication first, we find that D x E becomes 15 x 2, which is 30.
Working on the addition second, we need to then add C (which is 7) to this answer, which gives us an answer of 37.
Did you get those calculations in the right order maths coder?
• Question 7

If c = 7, d = 15 and e = 2, what is (c + d) ÷ e?

11
EDDIE SAYS
There are three operations present in this calculation: brackets, + and ÷.
According to the rules of BIDMAS, the sum in brackets (which contains the addition) is the highest priority and needs to be tackled first.
This means that the division (÷) is the lowest priority.
Working out the brackets first, we find that (c + d) becomes 7 + 15, which gives us a total of 22.
Working on the division second, we need to then divide this answer by e (which is 2), which gives us an overall answer of 11.
• Question 8

If c = 7, d = 15 and e = 2, what is c + d - e?

20
EDDIE SAYS
There are two operations present in this calculation: + and -.
According to the rules of BIDMAS, both of these operations have equal weight so we should work through the equation from left to right to reach the correct answer.
When we substitute the letters for the numbers they represent, c + d - e becomes 7 + 15 - 2.
If we work through this from left to right, we reach 22 - 2.
Therefore, the overall answer to this calculation is 20.
Don't be fooled and think that you must always use BIDMAS to solve problems.
• Question 9

When you see addition and subtraction in a calculation, what should you do according to the rules of BIDMAS

If both are present, you complete them from left to right
EDDIE SAYS
In BIDMAS, addition and subtraction are given equal weight in terms of priorities.
So if both appear in the same question, then you calculate steps from the left to right of the equation.
• Question 10

If a = 32, b = 2, c = 7, d = 15 and e = 4, what is b (a ÷ e) - c?

9
EDDIE SAYS
There are four operations present in this calculation: brackets, x, - and ÷.
According to the rules of BIDMAS, the sum in brackets (which contains the division) is the highest priority and needs to be tackled first.
The multiplication is the next priority and needs to be tackled second.
This means that the subtraction is the lowest priority.
Working out the brackets first, we find that a ÷ e becomes 32 ÷ 4, which gives us a total of 8.
Working on the multiplication second, we need to then times this answer by b (which is 2), which gives us an answer of 16.
Finally, we need to subtract c (which is 7) from this total, which leaves us with an overall answer of 9.
Phew, that was a long one with many steps! Well done for persevering.
---- OR ----

Sign up for a £1 trial so you can track and measure your child's progress on this activity.

### What is EdPlace?

We're your National Curriculum aligned online education content provider helping each child succeed in English, maths and science from year 1 to GCSE. With an EdPlace account you’ll be able to track and measure progress, helping each child achieve their best. We build confidence and attainment by personalising each child’s learning at a level that suits them.

Get started