well, first find "n" as followshttp://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_qp_63.pdf
Q 4 part (iii)
Dug
PhyZac
Please help guys
is the expected number is to 8 from n ,therefore, (the prob of getting a 3 ) 2/6 x n = 8
n = 24
now i hope u know this rule, that is npq is variance
n = 24
p = 2/6
q = 1 -p = 1 - (2/6) = 4/6
24 x 2/6 x 4/6 = 5.33