Question

What will come in the place of ‘?’ in the following equation, if ‘+’ and ‘÷’ are interchanged and ‘×’ and ‘–’ are interchanged? 15 ÷ 27 x 14 + 7 - 10 = ?

• A. 22
• B. 42
• C. 12
• D. 32

Answer 1

Answer:

A. 22

The value that will come in place of ‘?’ is 22.

• Interchange the signs as instructed:

  • Substitute ÷ with +

  • Substitute x with –

  • Substitute + with ÷

  • Substitute – with x

• Rewrite the equation with the new signs:
  $15 + 27 - 14 \div 7 \times 10 = ?$

• Apply the BODMAS / VBODMAS rule (Division $\rightarrow$ Multiplication $\rightarrow$ Addition $\rightarrow$ Subtraction):

  • Step 1 (Division): $14 \div 7 = \mathbf{2}$
    Equation becomes: $15 + 27 - 2 \times 10 = ?$

  • Step 2 (Multiplication): $2 \times 10 = \mathbf{20}$
    Equation becomes: $15 + 27 - 20 = ?$

  • Step 3 (Addition): $15 + 27 = \mathbf{42}$
    Equation becomes: $42 - 20 = ?$

  • Step 4 (Subtraction): $42 - 20 = \mathbf{22}$