Question

What will come in place of the question mark (?) in the following equation, if '+' and '—' are interchanged and also '×' and '÷' are interchanged?

8 - 13 + 18 ÷ 9 × 3 = ?

• A. -33
• B. 33
• C. 32
• D. -32

Answer 1

Answer:

A. -33

The value that will come in place of the question mark is -33.

First, interchange the signs according to the rules:

• + and - swap places (+ $\leftrightarrow$ -)

• × and ÷ swap places (× $\leftrightarrow$ ÷)

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1. Substituting the signs into the equation:

• Original: 8 - 13 + 18 ÷ 9 × 3 = ?

• Interchanged: 8 + 13 - 18 × 9 ÷ 3 = ?

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2. Solving using BODMAS rules:

• Step 1: Division (÷)

  • 9 ÷ 3 = 3

  • The equation becomes: 8 + 13 - 18 × 3

• Step 2: Multiplication (×)

  • 18 × 3 = 54

  • The equation becomes: 8 + 13 - 54

• Step 3: Addition and Subtraction (+ / -)

  • 8 + 13 = 21

  • 21 - 54 = -33