Question

4 coins are tossed simultaneously, the expected number of heads are
A. 1
B. 1.5
C. 3
D. 2

Answer 1

Hint: Clearly tossing of 4 coins are independent events which is an event that is not affected by previous events.we will also try to list out all the possible outcomes and then just multiply with 4.

Complete step by step answer:
A coin can possibly have 2 outcomes one can be head and another can be tail
Therefore, Probability of getting a head in one coin \[ = \dfrac{1}{2}\]
As total number of outcomes is 2 i.e., head or tail and we need one of these outcome that is head so we are getting \[\dfrac{1}{2}\] for one coin
Probability of not getting a head \[ = \dfrac{1}{2}\]
So we are given a total of 4 coins
Which means that the expected value will be
\[\begin{array}{l}
 = \dfrac{1}{2} \times 4\\
 = 2
\end{array}\]

So, the correct answer is “Option D”.

Note: Here we must see that the events are independent and the proper definition for that is Two events are independent if the result of the second event is not affected by the result of the first event. If A and B are independent events, the probability of both events occurring is the product of the probabilities of the individual events.