Question

Random variable X counts the number of times doubles is rolled (i.e. the same number comes up on both dice) when two ordinary (6-sided) fair dice are rolled seven times. How many possible values does X have?
a.6

b.7

c.8

d.30

e.36

Answer 1

So, We roll two die 7 times .

X is the number of times doubles is rolled .

Note that it may happen that , all the 7 rolls have distinct face value ,

it may also happpen that , all 7 rolls have doubles .

So X can take any value from 0,1,2,..,6,7

So, X can take 8 values .

Option C