Q. 2 - The Practice of Statistics for AP

Question

The probability distribution for the number of heads in four tosses of a coin is given by 

Number of heads	0	1	2	3	4
Probability	$0.0625$	$0.2500$	$0.3750$	$0.2500$	$0.0625$

The probability of getting at least one tail in four tosses of a coin is

 (a) $0.2500$. (b)$0.3125$ (c) $0.6875$ (d) $0.9375$ (d) None of these

Step-by-Step Solution

Answer

The probability of getting at least one tail in four tosses of a coin is option (d) $0.9375.$

Step 1: Given information

The probability distribution for the number of heads in four tosses of a coin is 

Number of heads	$1$	$2$	$3$	$4$	$5$
Probability	$0.0625$	$0.2500$	$0.3750$	$0.2500$	$0.9375$

Step 2: Explanation

Because the probability distribution provides you with the number of heads, you can figure out how many tails there are by performing$4-$(number of heads)

After that, you must add the probability of the tails together

Add $P\left(0\right)+P\left(1\right)+P\left(2\right)+P\left(3\right)$, the possibility of having at least one tail

$.0625+.2500+.3750+.25=.9375$

The correct option is (d).