Question

There are 20 stations from C.S.T. to THANE. How many different types of second class monthly season tickets must be printed in order that a passenger can purchase season ticket from any one station to another?

Answer 1

Answer:

380

Step-by-step explanation:

Hi,

Given there are 20 stations from CST and Thane

Let the stations from CST be A, B, C.......T

A passenger starting from CST can purchase a ticket up to

CST->A or CST->B or CST->C or...or CST->T, so a person

boarding at CST is having 19 different options.

Similarly, A passenger starting from station A towards Thane can

purchase a ticket up to  (A->B or A->C or ...or A-> T, so a person

boarding at A is having 18 different options , The same person

who is boarding at A can also purchase ticket to(A-> CST) hence

there are 19 possible ways of purchasing ticket.

Continuing in this manner , we can observe that at every station

there are sum total of 19 possible ways of purchasing a ticket

either from that station to any other station towards Thane or to

any station towards CST.

So, we find at each station there are 19 options a passenger

could purchase so for a total of 20 stations, there should be

20*19 = 380 types of season tickets.

Hope, it helps !