Question 1122438
Two identical cubes each having faces numbered from 0 to 5 are rolled. A score for the roll is determined as the product of the two numbers on the two uppermost faces. 
 a) The cubes are rolled once. What is the probability that the score is i) 0?
(1/6)*(1/6) = 1/36
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 ii) at least 15?
0, 1 & 2 are not allowed.
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3*5
4*4
4*5
5*3
5*4
5*5
--> 6/36 = 1/6
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 b) If both cubes are rolled twice and the scores for each roll are added, what is the probability of a combined score of at least 45?
Neither can be less than 20.
4*5 + 5*5
5*5 + 4*5
5*5 + 5*5
--> 3/36 = 1/12