Question

You flip a coin twice. find the probability that at least one of the tosses showed heads.

a. 13
b. 34
c. 14
d. 12

Answer 1

`\text{P(At least one head) = 1 - P(TT)}`


`\text{P(TT)} = ((1)/(2))^(2)`

`\text{P(At least one head)} = 1 - (1)/(4)`

`= (3)/(4)`

Answer 2

This is equivalent to

P(H then H))
+ P(t then H)
+ P(H then T)

= 3( 1/2 *1/2)

= 3/4