Correct Answer: –, ÷, +, ×, =

Solution : Given:
17 * 21 * 7 * 5 * 4 * 34

Replace * with the mathematical signs and solve the equations one by one using the BODMAS.
Let's check the options –
First option: ÷, –, +, ×, =
⇒ 17 ÷ 21 – 7 + 5 × 4 = 34
Solving the L.H.S. of the equation –
= 0.81 – 7 + 5 × 4
= 0.81 – 7 + 20
= 20.81 – 7
= 13.81 ≠ 34
Second option: –, ÷, +, ×, =
⇒ 17 – 21 ÷ 7 + 5 × 4 = 34
Solving the L.H.S. of the equation –
= 17 – 3 + 5 × 4
= 17 – 3 + 20
= 37 – 3
= 34 = R.H.S.
Third option: +, ×, ÷, –, =
⇒ 17 + 21 × 7 ÷ 5 – 4 = 34
Solving the L.H.S. of the equation –
= 17 + 21 × 1.4 – 4
= 17 + 29.4 – 4
= 46.4 – 4
= 42.4 ≠ 34
Fourth option: ×, –, ÷, +, =
⇒ 17 × 21 – 7 ÷ 5 + 4 = 34
Solving the L.H.S. of the equation –
= 17 × 21 – 1.4 + 4
= 357 – 1.4 + 4
= 361 – 1.4
= 359.6 ≠ 34

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