Question 8:
Diagram 4 shows a dart’s target board at a dart game booth in a funfair.
Diagram 4
The booth offers 3 darts per game. The customers have to pay RM5 to play a game. A toy bear will be given to customers who are able to hit the bullseye for the three darts’ throws in a game. Bob is a dart player. By average, he hits the bullseye 7 times out of 10 darts thrown.
(a) Bob would play the game if he had at least 90% chance to win at least one toy bear by spending RM30.
By mathematical calculation, suggest to Bob whether he should play the game or otherwise. [4 marks]
(b) What is the minimum number of games that Bob needed so that he can get 4 toy bears? [4 marks]
Solution:
(a)
By playing 6 games, Bob had at least 90% chance to win at least one toy bear. Hence, Bob should play the game.
(b)
np ≥ 4
n(0.343) ≥ 4
n ≥ 11.66
n = 12
Minimum number of games = 12
Diagram 4 shows a dart’s target board at a dart game booth in a funfair.
Diagram 4The booth offers 3 darts per game. The customers have to pay RM5 to play a game. A toy bear will be given to customers who are able to hit the bullseye for the three darts’ throws in a game. Bob is a dart player. By average, he hits the bullseye 7 times out of 10 darts thrown.
(a) Bob would play the game if he had at least 90% chance to win at least one toy bear by spending RM30.
By mathematical calculation, suggest to Bob whether he should play the game or otherwise. [4 marks]
(b) What is the minimum number of games that Bob needed so that he can get 4 toy bears? [4 marks]
Solution:
(a)
By playing 6 games, Bob had at least 90% chance to win at least one toy bear. Hence, Bob should play the game.
(b)
np ≥ 4
n(0.343) ≥ 4
n ≥ 11.66
n = 12
Minimum number of games = 12