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Exam
Numerical Ability
Probability
Suppose a fair six -sided die is rolled once. If the value on the die is 1, 2, or 3, the die is rolled a second time. What is the probability that the sum total of values that turn up is at least 6?
option
(A) 10/21
(B) 5/12
(C) 2/3
(D) 1/6
Read Solution (Total 3)
-
- 5/12....9/36+1/6
(1,5)(1,6)(2,4)(2,5)(2,6)(3,3)(3,4)(3,5)(3,6)=9
1/6->first time we get 6 - 9 years agoHelpfull: Yes(0) No(0)
- If the value on dice is 1,2 or 3 it is rolled again so totally the sample space is 6*3+3=21, and 9 events of throwing the dice twice obtaining sum greater than 6 and a single event of obtaining 6 (all the possible events are (1,5) (1,6) (2,4) (2,5) (2,6) (3,3) (3,4) (3,5) (3,6), and 6)the number of events is 10. So probability= 10/21
- 7 years agoHelpfull: Yes(0) No(1)
- Sample space is S= { (1,1), (1,2),(1,3), (1,4),(1,5), (1,6),(2,1), (2,2),(2,3), (2,4),(2,5), (2,6),(3,1), (3,2),(3,3), (3,4),(3,5),(3,6),4,5,6}
Event is sum should be at least 6
E={ (1,5),(1,6),(2,4),(2,5),(2,6),(3,3),(3,4),(3,5),(3,6),6}
so 10/21 - 6 years agoHelpfull: Yes(0) No(0)
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