Which two signs need to be interchanged to make the following equation correct?

3 × 10 + 3 − 21 ÷ 3 = 34

+ and -

For every type of Mathematical operations question, you must know only one rule i.e. BODMAS. It is “Brackets, Orders, Division, Multiplication, Addition, and Subtraction. It means you must solve any equation in the BODMAS order. First, open the brackets, then solve the powers or roots, then perform Division followed by multiplication, Addition and subtraction.

Applying the required changes.

Option 2

LHS

= 3 × 10 - 3 + 21 ÷ 3

= 30  - 3 + 7

= 34.

∴ LHS = RHS

So, Option 2 is the required answer.