Correct Answer: –, ÷, ×, =

Solution : Given:
23 * 2 * 2 * 5 * 18

Replace * with the mathematical signs and solve the equations one by one.
Let's check the given options –
First option: –, ÷, ×, =
23 – 2 ÷ 2 × 5 = 18
Solving the L.H.S of the equation –
= 23 – 2 ÷ 2 × 5
= 23 – 1 × 5
= 23 – 5
= 18
L.H.S. = R.H.S.
Second option: –, ÷, +, =
23 – 2 ÷ 2 + 5 = 18
Solving the L.H.S of the equation –
= 23 – 2 ÷ 2 + 5
= 23 – 1 + 5
= 28 – 1
= 27
LHS ≠ RHS
Third option: –, ÷, =, +
23 – 2 ÷ 2 = 5 + 18
Solving the L.H.S of the equation –
= 23 – 2 ÷ 2
= 23 – 1
= 22
Solving the R.H.S of the equation –
= 5 + 18
= 23
LHS ≠ RHS
Fourth option: –, ×, ÷, =
23 – 2 × 2 ÷ 5 = 18
Solving the L.H.S of the equation –
= 23 – 2 × 2 ÷ 5
= 23 – 2 × 0.4
= 23 – 0.8
= 22.2
LHS ≠ RHS

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