Question

What will come in place of the question mark (?) in the following equation if ‘+’ and ‘÷’ are interchanged and also ‘×’ and ‘–’ are interchanged?

42 + 7 ÷ 24 × 6 – 3 = ?

• A. 14
• B. 12
• C. 13
• D. 10

Answer 1

Answer:

B. 12

The correct answer is 12.

1. Identify the interchanges required by the question:

   • Interchange $+$ and $\div$ (so $+$ becomes $\div$ and $\div$ becomes $+$)

   • Interchange $\times$ and $-$ (so $\times$ becomes $-$ and $-$ becomes $\times$)

2. Rewrite the original equation with the interchanged signs:

   • Original: $42 + 7 \div 24 \times 6 - 3 = ?$

   • New Equation: $42 \div 7 + 24 - 6 \times 3 = ?$

3. Solve the expression following the BODMAS rule (Division $\rightarrow$ Multiplication $\rightarrow$ Addition $\rightarrow$ Subtraction):

   • Perform Division:
     $42 \div 7 = 6$
     The equation becomes: $6 + 24 - 6 \times 3$

   • Perform Multiplication:
     $6 \times 3 = 18$
     The equation becomes: $6 + 24 - 18$

   • Perform Addition:
     $6 + 24 = 30$
     The equation becomes: $30 - 18$

   • Perform Subtraction:
     $30 - 18 = 12$