Question
SLPaper 2
A six-sided biased cube is weighted in such a way that the probability of obtaining a “six” is .
1.[3]
The cube is tossed five times. Find the probability of obtaining at most three "sixes".
Verified
Solution
recognition of binomial (M1)
X ~ B(5, 0.7)
attempt to find P (X ≤ 3) (M1)
=0.472 (= 0.47178)*(A1)
[3 marks]
2.[3]
The cube is tossed five times. Find the probability of obtaining the third "six" on the fifth toss.
Verified
Solution
recognition of 2 sixes in 4 tosses (M1) P (3rd six on the 5th toss) A1 = 0.185 (= 0.18522) A1 [3 marks]