
Chapter 5
PB
Probability
193
5.7.7 Independent Events
Two events E
1
and E
2
are said to be independent if the following condition exists:
P(E
1
/E
2
) = P(E
1
) and P(E
2
/E
1
) = P(E
2
)
When two events E
1
and E
2
are independent, then conditional probability is solved as marginal
probability. Independence is a very important property, and with the help of Example 5.16, we
can understand its importance.
Example 5.16
Delta is a leading marketing research rm in India. A client of Delta is interested in the proba-
ble relationship between telephone and television purchase of a particular region. The company
prepared a single question “Do you have a telephone and/or ...