Answer:

Explanation:
We are give that three coins are flipped
Then , the sample space={HHH,HHT,THH,HTH,TTH,HTT,THT,TTT}
We have to find the probability of obtaining atleast one head
Atleas one head it means equal 1 or more than 1 head
Favorable cases={HHH,HHT,THH,HTT,HTH,TTH,THT}
Total number of cases=8
Number of favorable cases=7
Probability,P(E)=

Using the formula
The probability of obtaining atleast one head=
