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1.1 I) BODMAS/ BIDMAS – Part 1

Whenever we have a calculation, we need to make sure that we complete it in the correct order. An easy way to remember the correct order is to use BODMAS or BIDMAS; it does not matter which one of these you remember.
 
The order that we must complete our calculation using BODMAS is:

• Brackets
• Other
• Division
• Multiplication
• Addition
• Subtraction

 
The letters in BIDMAS mean the same as the letters in BODMAS, except the I in BIDMAS means indices and not other. 
 
Let’s have a few examples.

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Example 1

Complete the calculation below:

To make sure that we complete the above calculation correctly, we are going to use BODMAS. There are no brackets in this calculation, which means that we can go onto the other/ indices. Therefore, we need to work out what 5² is, and 5² is 25 (5 x 5). This means that we can replace 5² with 25. The calculation becomes:

We are now onto D, which is division. There is no division in the calculation, so we move onto the next letter in BODMAS, which is M. M stands for multiplication, so we work out what 7 x 3 is, which is 21. The calculation becomes:

We now move onto A, which is addition; 10 + 25, which is 35.

And finally, we are onto the S, which is subtraction; 35 – 21, which is 14.

Therefore, the answer to this calculation is 14.

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Example 2

Complete the calculation below.

We start with the B in BODMAS, which is the brackets. As there are no brackets, we move onto the O, which is other or indices; we calculate 7² (49) and 4² (16).

The next step is to complete the division; 16 ÷ 2.

Then the multiplication; 6 x 4.

Next, we work out the addition; 49 + 24.

Finally, we work out the subtraction; 73 – 8.

Therefore, the answer to this calculation is 65.