HSC Board Paper Solutions Check Your Mark

Sunday, March 23, 2014

Two coins are tossed simultaneously. Write the sample space 'S' and the number of sample points n(S). Write the following events using set notation and mention the total number of elements in each of them: a. A is the event of getting at least one head. b. B is the event of getting exactly one head.

iii. Two coins are tossed simultaneously. Write the sample space 'S' and the number of sample points n(S). Write the following events using set notation and mention the total number of elements in each of them:

a. A is the event of getting at least one head.

b. B is the event of getting exactly one head.



Answer: Since two coins are tossed simultaneously



{
H
H

Sample Space is
=

H
T




T
H




T
T
}

n(S) = 4

(a) Let A = Event that at least one head turns up

A = {HH, HT,  TH, }

n(A) = 3

P(A)
=
n(A)








n(S)














P(A)
=
   3








   4






(b) Let B = Event of getting Exactly one head turns up

B = {HT, TH}

n(B) = 2

P(B)
=
n(B)



n(S)




P(B)
=
   2



   4

P(B)
=
   1



   2