By interchanging the two signs ÷ and + and two numbers 9 and 12 (NOT digits), which of the following equations will NOT be correct?
I. $$12\times2-72+9\div57=69$$
II. $$169+13\times12\div3-9=108$$

According to question make changes in / and + , 9 and 12 :
$$12\times\ 2\ -\ 72\ +\ \frac{9}{57}=69$$

$$\frac{169}{13}\times\ 9+3-12=108$$

We need to make changes in both the equation and solve it 
$$12\times\ 2\ -\ 72\ +\ \frac{9}{57}=69$$

$$9\times\ 2\ -\ \frac{72}{12}+57=69$$

$$18-\frac{72}{12}+57=69$$

$$18-6+57=69$$

$$12+57=69$$

$$69=69$$

$$\frac{169}{13}\times\ 9\ +\ 3\ -\ 12=108$$

$$13\times\ 9\ +\ 3-12=108$$

$$117+\ 3-12=108$$

$$120-12=108$$

$$108=108$$

According to this L.H.S=R.H.S Hence option A is the correct answer.