Question

(4) simultaneously throw of pair of dice, find the probability
(1) sum is 8 (ii) doublet ii) a sum less than a (ar) product 12
v)neither 5 on the dice
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Answer 1

i) answer : 5/36

Explanation : 8 will be the sum when one amongst these 5 pairs appear on die i.e. (2,6),(3,5),(4,4),(5,3),(6,2) and the total no. of outcomes while rolling die is 36

ii) 6/36 = 1/6

Explanation : doublets are (1,1),(2,2),(3,3),4,4),(5,5),(6,6)

iii) 4/36 = 1/9

Explanation : product will be 12 if following pair appears: (2,6),(3,4),(4,3),(6,2)

iv) 25/36

Explanation : 1 - no. of times 5 appear on die

No. of times 5 appear on die = 11

Therefore, 1 - (11/36) = 25/36