sung is three blocks east and five blocks south of ther freinds home . how many different routs are possible if she walks only west or north

Dear student,

you can assume position of sung to be (0,0)

form given data it is clear that her destination point is (3,5)

so she has to take 3 steps towards west and 5 towards north and both are mutually exclusive

=> total number of routes possible are = 3*5 = 15