Question

Which two signs and two numbers should be interchanged in the following equation to make it correct?

23 × 13 - 195 ÷ 17 + 40 = 366

1. 23 and 40, × and -
2. 23 and 17, × and ÷
3. 13 and 17, × and +
4. 13 and 17, + and -

Answer 1

Correct Answer - Option 4 : 13 and 17, + and -

23 × 13 - 195 ÷ 17 + 40 = 366

Let's check each option one by one:

Option 1) 23 and 40, × and -

LHS

40 - 13 × 195 ÷ 17 + 23

= 40 -149.11 +23

= 86.11 = RHS

LHS = 336

Since, LHS ≠ RHS

Option 1) is not true.

Option 2)  23 and 17, × and ÷

23 × 13 - 195 ÷ 17 + 40 = 366

LHS
17 ÷ 13 - 195 ×  23 + 40 

= 1.30 - 4485 + 40

= - 4443.7

RHS = 336

Since, LHS ≠ RHS

Option 2) is not true.

Option 3) 13 and 17, × and +

23 × 13 - 195 ÷ 17 + 40 = 366

LHS

= 23 + 17 - 195 ÷ 13 × 40

= 40 - 15 × 40

= 40 - 600

= 560

RHS = 336

Since, LHS ≠ RHS

Option 3) is not true.

Option 4) 13 and 17, + and -

23 × 13 - 195 ÷ 17 + 40 = 366

LHS

= 23 × 17 + 195 ÷ 13 - 40

= 391 + 15 - 40

= 406 - 40

= 366

RHS = 366

Since, LHS = RHS

Option 4) is correct.

Hence, 13 and 17, + and - is correct.