there are 28 stations between hyderabad and bangalore. how many second class tickets have to be printed, so that a passenger can travel from any station to any other station?	Choose one
A) 156
B) 167
C) 870
D) 352
E) 380
<gadget id="calculator">28 + 1</gadget>
<output>29</output>

<gadget id="calculator">29 + 1</gadget>
<output>30</output>

<gadget id="calculator">29 * 30</gadget>
<output>870</output>

<result>C</result>
there are 28 stations between hyderabad and bangalore. how many second class tickets have to be printed, so that a passenger can travel from any station to any other station?
multiply(add(28, const_1), add(add(28, const_1), const_1))
"the total number of stations = 30 from 30 stations we have to choose any two stations and the direction of travel ( i . e . , hyderabad to bangalore is different from bangalore to hyderabad ) in 3 ⁰ p ₂ ways . 30 p ₂ = 30 * 29 = 870 . answer : c"