Correct Answer: × and –

Solution : Given:
39 – 3 ÷ 13 + 16 × 8 = 17

Let's check the options –
First option: × and –
39 – 3 ÷ 13 + 16 × 8 = 17
On interchanging the mathematical signs, we get –
⇒ 39 × 3 ÷ 13 + 16 – 8 = 17
⇒ 9 + 16 – 8
⇒ 25 – 8
⇒ 17
Second option: + and –
39 – 3 ÷ 13 + 16 × 8 = 17
On interchanging the mathematical signs, we get –
⇒ 39 + 3 ÷ 13 – 16 × 8 = 17
⇒ 39 + 0.23 – 16 × 8
⇒ 39 + 0.23 – 128
⇒ – 88.77 ≠ 17
Third option: ÷ and –
39 – 3 ÷ 13 + 16 × 8 = 17
​​​​​​​On interchanging the mathematical signs, we get –
⇒ 39 ÷ 3 – 13 + 16 × 8 = 17
⇒ 13 – 13 + 16 × 8
⇒ 13 – 13 + 128
⇒ 128 ≠ 17
Fourth option: × and ÷
39 – 3 ÷ 13 + 16 × 8 = 17
​​​​​​​On interchanging the mathematical signs, we get –
⇒ 39 – 3 × 13 + 16 ÷ 8 = 17
⇒ 39 – 3 × 13 + 2
⇒ 39 – 39 + 2
⇒ 2 ≠ 17

Here, only the first option satisfies the R.H.S. of the equation. Hence, the first option is correct.