Question : Directions: Which two numbers (NOT digits) should be interchanged to make the following equation mathematically correct?
8 ÷ 2 × 6 − 11 + 5 = 15
Option 1: 2 and 8
Option 2: 5 and 6
Option 3: 2 and 6
Option 4: 6 and 11
Correct Answer: 5 and 6
Solution :
Given:
8 ÷ 2 × 6 − 11 + 5 = 15
Let's check each option –
First Option:
2 and 8
On interchanging the numbers, we get –
2 ÷ 8 × 6 − 11 + 5 = 15
On solving the L.H.S. of the equation –
= 2 ÷ 8 × 6 − 11 + 5
= 1.5 − 11 + 5
= –4.5 ≠ 15
Second Option:
5 and 6
On interchanging the numbers, we get –
8 ÷ 2 × 5 − 11 + 6 = 15
On solving the L.H.S. of the equation –
= 8 ÷ 2 × 5 − 11 + 6
= 4 × 5 − 11 + 6
= 20 − 11 + 6
= 15
Third Option:
2 and 6
On interchanging the numbers, we get –
8 ÷ 6 × 2 − 11 + 5 = 15
On solving the L.H.S. of the equation –
= 8 ÷ 6 × 2 − 11 + 5
= 2.67 − 11 + 5
= –3.33 ≠ 15
Fourth Option:
6 and 11
On interchanging the numbers, we get –
8 ÷ 2 × 11 − 6 + 5 = 15
On solving the L.H.S. of the equation –
= 8 ÷ 2 × 11 − 6 + 5
= 4 × 11 − 6 + 5
= 44 − 6 + 5
= 43 ≠ 15
So, only the second option satisfies the equation. Hence, the second option is correct.
Related Questions
Know More about
Staff Selection Commission Multi Tasking ...
Application | Cutoff | Selection Process | Preparation Tips | Eligibility | Exam Pattern | Admit Card
Get Updates Brochure
Your Staff Selection Commission Multi Tasking Staff Exam brochure has been successfully mailed to your registered email id “”.
