Correct Answer: 3 × 2 – 72 ÷ 6 + 8 = 18

Solution : Let's check the options –
First option: 8 ÷ 4 × 6 + 5 – 9 = 16
On interchanging the given signs, the equation becomes –
⇒ 8 ÷ 4 × 6 – 5 + 9 = 16
Solving the L.H.S. of the equation –
= 2 × 6 – 5 + 9
= 12 – 5 + 9
= 21 – 5
= 16
Second option: 15 + 3 × 4 – 6 ÷ 2 = 6
On interchanging the given signs, the equation becomes –
⇒ 15 – 3 × 4 + 6 ÷ 2 = 6
Solving the L.H.S. of the equation –
= 15 – 3 × 4 + 3
= 15 – 12 + 3
= 18 – 12
= 6
Third option: 3 × 2 – 72 ÷ 6 + 8 = 18
On interchanging the given signs, the equation becomes –
⇒ 3 × 2 + 72 ÷ 6 – 8 = 18
Solving the L.H.S. of the equation –
= 3 × 2 + 12 – 8
= 6 + 12 – 8
= 18 – 8
= 10 ≠ 18
Fourth option: 3 + 4 – 2 × 5 ÷ 1 = 9
On interchanging the given signs, the equation becomes –
⇒ 3 – 4 + 2 × 5 ÷ 1 = 9
Solving the L.H.S. of the equation –
= 3 – 4 + 2 × 5
= 3 – 4 + 10
= 13 – 4
= 9

So, only the equation in the third option does not satisfy the R.H.S. of the given equation. Hence the third option is correct.