Table 2 shows the 300 employees of a glass manufacturing company cross-classified on the basis of age and department. All answers must be rounded to three (3) decimal places for this question.

Table 2

Age	Department	Total
Production	Sales	Administration
<30	60	25	18	103
30-50	70	29	25	124
>50	30	8	35	73
Total	160	62	78	300

An employee is selected at random from the glass manufacturing company.

a)What is the probability that the selected employee comes from the Sales Department or who is under 30 years of age?

Answer: 62/300+103/300-25/300=0.467

May I know why do we need to minus 25/300 here??