Question

Three men start together to travel the same way round a circular track of $13km$. Their speeds are $5,6.5$ and $9km/hr$ respectively. When will they meet at the starting point?

• A. $21$ hrs
• B. $26$ hrs
• C. $6\frac{1}{2}hrs$
• D. $19\frac{1}{2}hrs$

Answer 1

The correct option is B $26$ hrs

Time for one revolution by each of man $=\frac{13}{5},\frac{13}{\frac{13}{2}},\frac{13}{9}=\frac{13}{5},\frac{2}{1},\frac{13}{9}$
$\therefore Thetimewhentheywillmeetatthestartingpoint=L.C.Mof\frac{13}{5},\frac{2}{1},\frac{13}{9}=\frac{26}{1}h$
Hence They will meet at Starting point after $26h$