Three similar coins were tossed simultaneously for 100 times and the data recorded is as given below :
No of heads0123No of tosses = Frequency10354015
(i) What is the probability of getting more tails than heads?
(ii) What is the probability of getting more heads than tails?
(iii) Are (i) and (ii) complementary? Will they be complementary if we had 4 coins? [4 MARKS]
Three similar coins were tossed simultaneously for 100 times and the data recorded is as given below :
No of heads0123No of tosses = Frequency10354015
(i) What is the probability of getting more tails than heads?
(ii) What is the probability of getting more heads than tails?
(iii) Are (i) and (ii) complementary? Will they be complementary if we had 4 coins? [4 MARKS]
Concept: 1 Mark
Solution: 1Mark each
For getting more tails than heads, the favourable outcomes are 0 heads and 1 head.
Probability = (10 + 35)/100 = 0.45.
For getting more heads than tails, the favourable outcomes are 2 heads and 3 heads.
Probability = (40 + 15)/100 = 0.55.
These two events are complementary in this particular case. But they won’t be complementary, say, when you have four coins, because you would then have a third alternative of getting an equal number of heads and tails.
Concept: 1 Mark
Solution: 1Mark each
For getting more tails than heads, the favourable outcomes are 0 heads and 1 head.
Probability = (10 + 35)/100 = 0.45.
For getting more heads than tails, the favourable outcomes are 2 heads and 3 heads.
Probability = (40 + 15)/100 = 0.55.
These two events are complementary in this particular case. But they won’t be complementary, say, when you have four coins, because you would then have a third alternative of getting an equal number of heads and tails.
