Correct Answer: +, –, +, –, =

Solution : Given:
74 * 34 * 78 * 23 * 23 * 30

Replace the * sign given in the equation with the assigned signs in the options one by one –
First option: ÷, –, +, ×, =
74 ÷ 34 – 78 + 23 × 23 = 30
Solving the L.H.S. of the equation –
= 2.17 – 78 + 23 × 23
= 2.17 – 78 + 529
= 453.17 ≠ 30
Second option: +, ÷, ×, –, =
74 + 34 ÷ 78 × 23 – 23 = 30
Solving the L.H.S. of the equation –
= 74 + 0.435 × 23 – 23
= 74 + 10.005 – 23
= 61.005 ≠ 30
Third option: +, –, +, –, =
74 + 34 – 78 + 23 – 23 = 30
Solving the L.H.S. of the equation –
= 131 – 101
= 30
Fourth option: –, ÷, +, ×, =
74 – 34 ÷ 78 + 23 × 23 = 30
Solving the L.H.S. of the equation –
= 74 – 0.435 + 23 × 23
= 74 – 0.435 + 529
= 602.565 ≠ 30

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