Working Problems: $4.$ A city railway network has for sale one$-$way tickets for travel from one station to another station. Each ticket specifies the origin and destination. Several $($more than one$)$ new stations were added to the network, and an additional $76$ different ticket types had to be printed. How many new stations were added to the network? Note. This is still a working problem, and to get the marks you need to submit your reasoning as to why your answer to the question is correct.