Discussion Forum

1)

Five cities P, Q, R, S and T are connected by different modes of transport as follows:

P and Q are connected by boat as well as by rail.

S and R are connected by bus and by boat.

Q and T are connected only by air .

P and R are connected only by boat.

T and R are connected by rail and by bus.

If the person visits each of the places starting from P and gets back to P, which of the following places must he visit twice?

Answer:

Option B

Explanation:

If a person wants to visit all the places and again return to P, then he can go in the order of

$P\rightarrow Q$$\rightarrow T$$\rightarrow R$$\rightarrow S$ and then

$S\rightarrow R\rightarrow P$(OR)

$P\rightarrow R\rightarrow S$ and then

$S\rightarrow R\rightarrow T\rightarrow Q\rightarrow P $

He must visit R twice.