2. A box contains the following numbered tickets: 1,1,5,9,9
a) If I draw two tickets with replacement, what is the chance
that the sum of the two tickets is greater
than or equal to 10?
b) Drawing three tickets without replacement, what is the chance
the first two tickets are not 5's, and
the last ticket is a 5?
c) Calculate b) if the draws are made with replacement.
d) If I repeat the procedure in a) 8 times (ie draw 2 tickets
and find their sum, and do this 8 times), what
is the chance that I get a sum greater than or equal to 10
exactly 6 of the 8 times?