Question

The order of operations says to multiply and divide before you add and subtract. Why do you subtract before you multiply when you solve the equation?

Answer 1

Order Of Operation — Also known as BODMAS says to solve Bracket first then Roots or Exponents, Divide, Multiply, Add and finally Subtract.

However, while solving an equation we need to multiply before subtraction isn't always necessary.

For Example :-

• ➸ 3 + 2(12 - 6)

Here we need to solve the brackets first and in order to solve the brackets we need to subtract before multiplying.

As we know (12 - 6 = 6) so,

➔ 3 + 2 × 6

➔ 3 + 12

➔ 15

In the equation above, we subtracted 6 from 12 before multiplying 2 with it that was because (12 - 6) were inside brackets.

Taking Another Example :-

• ➸ 10 - 6 ÷ (1 + 2)

Solving Brackets first, (1 + 2 = 3)

➔ 10 - 6 ÷ 3

➔ 10 - 2

➔ 8

In the second example, we added 1 & 2 before dividing 6 by it that was because (1 + 2) were inside brackets.

Thus,

Following Order Of Operation (BODMAS) doesn't always means to multiply before subtraction, we can Subtract first if the number to be subtracted is inside Brackets.

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