Correct Answer: – and ÷

Solution : Given:
3 × 12 – 6 ÷ 2 + 12 = 16

Let's check the options –
First option: ÷ and +
On interchanging the signs, the equation becomes –
3 × 12 – 6 + 2 ÷ 12 = 16
Solving the L.H.S. of the equation –
= 3 × 12 – 6 + 0.167
= 36 – 6 + 0.167
= 30.16 ≠ 16
Second option : × and ÷
On interchanging the signs, the equation becomes –
3 ÷ 12 – 6 × 2 + 12 = 16
Solving the L.H.S. of the equation –
= 0.25 – 6 × 2 + 12
= 0.25 – 12 + 12
= 0.25 ≠ 16
Third option: – and ÷
On interchanging the signs, the equation becomes –
3 × 12 ÷ 6 – 2 + 12 = 16
Solving the L.H.S. of the equation –
= 3 × 2 – 2 + 12
= 6 – 2 + 12
= 16
Fourth option: – and +
On interchanging the signs, the equation becomes –
3 × 12 + 6 ÷ 2 – 12 = 16
Solving the L.H.S. of the equation –
= 3 × 12 + 3 – 12
= 36 + 3 – 12
= 39 – 12
= 27 ≠ 16

So, only the third option satisfies the given equation. Hence, the third option is correct.