Question

What will come in the place of ‘?’ in the following equation, if ‘−’ and ‘÷’ are interchanged and ‘×’ and ‘+’ are interchanged? 55 ÷ 25 – 5 + 15 × 10 = ?

• A. 10
• B. -25
• C. -10
• D. -20

Answer 1

Answer:

C. -10

The correct value for the question mark is -10.

1. Understand the Operation Interchanges:

   • Interchange − and ÷ (wherever ÷ appears, use −, and vice versa).

   • Interchange × and + (wherever + appears, use ×, and vice versa).

2. Rewrite the Equation:

   • Original equation: 55 ÷ 25 – 5 + 15 × 10 = ?

   • Transformed equation: 55 - 25 ÷ 5 × 15 + 10 = ?

3. Solve Using BODMAS/PEMDAS Rules:

   • Division: 25 ÷ 5 = 5

     • Equation becomes: 55 - 5 × 15 + 10

   • Multiplication: 5 × 15 = 75

     • Equation becomes: 55 - 75 + 10

   • Addition & Subtraction (from left to right):

     • 55 - 75 = -20

     • -20 + 10 = -10