total number of students = 51
total number of accounting students = 23
total number of chemistry student = 17
number of students that takes both accounting and chemistry = 4
total number of probabilities = 23 + 17 - 4
= 36
the probability of randomly chosen student taking accounting or chemistry
= 36/51
= 12/17
therefore, the probability of randomly chosen student taking accounting or chemistry is 12/17
