Experts Please explain this part

Dear Student,


As Given the 
Time take by the car to travel Distance $\frac{2AB}{\sqrt{3}}$ m = 6 second

So, Time taken by car to travel distance 1 m = $\frac{6}{{\displaystyle \frac{2AB}{\sqrt{3}}}} =\frac{3\sqrt{3}}{AB}$ second

So, Time taken by car to travel distance $\frac{AB}{\sqrt{3}}$ m =$\frac{3\sqrt{3}}{AB}\times \frac{AB}{\sqrt{3}} =3 second$


Regards