Select the number that will come in the place of the question mark (?), if ‘+’ and ‘–’ are interchanged and ‘×’ and ‘÷’ are interchanged in the expression: 11 ÷ 12 – 78 × 6 + 57 = ?

Question

Accepted Answer

Let's analyze the question step-by-step:

Original expression: 11 ÷ 12 – 78 × 6 + 57

Given:
- '+' and '–' are interchanged
- '×' and '÷' are interchanged

So, replace:
- '+' with '–'
- '–' with '+'
- '×' with '÷'
- '÷' with '×'

So, the new expression becomes:
11 × 12 + 78 ÷ 6 – 57

Now, let's solve using BODMAS:
First, multiplication and division:
- 11 × 12 = 132
- 78 ÷ 6 = 13

So, the expression is:
132 + 13 – 57

Now, addition and subtraction from left to right:
- 132 + 13 = 145
- 145 – 57 = 88

Wait, this gives 88, but let's double-check the operator mapping:

Let's carefully re-map each operator:
- The first '÷' (between 11 and 12) becomes '×' → 11 × 12
- The first '–' (between 12 and 78) becomes '+' → 12 + 78
- The '×' (between 78 and 6) becomes '÷' → 78 ÷ 6
- The '+' (between 6 and 57) becomes '–' → 6 – 57

But the original expression is: 11 ÷ 12 – 78 × 6 + 57
So, the mapping should be:
- 11 ÷ 12 → 11 × 12
- – 78 → + 78
- × 6 → ÷ 6
- + 57 → – 57

So, the new expression is:
11 × 12 + 78 ÷ 6 – 57

Now, let's solve:
Step 1: 11 × 12 = 132
Step 2: 78 ÷ 6 = 13
So, 132 + 13 – 57
Step 3: 132 + 13 = 145
Step 4: 145 – 57 = 88

But the options say 88 is option 4, but the answer key says 83 is correct. Let's check if the mapping is correct.

Wait: Let's try mapping as per the order in the original expression:
- 11 ÷ 12 – 78 × 6 + 57
- '÷' → '×', so 11 × 12
- '–' → '+', so + 78
- '×' → '÷', so ÷ 6
- '+' → '–', so – 57

So, the expression is:
11 × 12 + 78 ÷ 6 – 57

But this is the same as above.

So, 11 × 12 = 132
78 ÷ 6 = 13
132 + 13 = 145
145 – 57 = 88

So, the correct answer is 88 (option 4), not 83. The answer key must be incorrect.

Final Answer: 88 (Option 4).

Answer

Answer

Answer