Question

A coin is tossed for a certain no. of times . If the probability of getting a head is 0.4 and the head appeared up for 24 times , find the no. Of times coin tossed. Hence, find the probability of getting a tail and verify that P(H)+P(T)=1

Answer 1

Let no. of times the coin is tossed= "x"
also 0.4 = 4/10 
no. of times head = 24
now,
⇒4/10=24/x
⇒x/10=24/4
⇒x=6*10
x=60
So the number of times the coin is tossed= 60

Probability of getting a tail = (60 - 24)/60
                                           = 36/60

Now,
P(H)+P(T)=1
BECAUSE
⇒24/60 + 36/60
⇒(24+36)/60
⇒60/60=1
             VERIFIED

Answer 2

Given,

P(H) = 0.4

Number of times head comes up = 24

To find,

We have to find the number of times a coin is tossed and the probability of getting a tail and verify that  P(H)+P(T)=1.

Solution,

The total number of times a coin is tossed is 60 times and the probability of getting a tail is 0.6.

We can simply find the number of times a coin is tossed by using the formula of probability.

Let the number of times a coin is tossed be x.

Probability of getting a head = 0.4

4/10 = 24/x

x = 60

So, the total number of times a coin is tossed is 60 times.

Number of times of getting a tail = 60-24

                                                          = 36

P ( of getting a tail ) = 36/60

                                 = 0.6

P(H) = 0.4

P(T) = 0.6

P(H) +P(T) =1

0.4 +0.6 = 1

Hence verified that P(H)+P(T)=1.

Hence, the total number of times a coin is tossed is 60 times and the probability of getting a tail is 0.6.