Answer:
72.25%; 23.16%; 76.84%; No.
Step-by-step explanation:
The probability that any given cheese chosen at random will be pasteurized is 85%, or 0.85.
This means that the probability of two random cheeses being pasteurized will be
0.85(0.85) = 0.7225 = 72.25%.
The probability that 9 cheeses chosen at random will all be pasteurized will be
0.85⁹ = 0.2316 = 23.16%.
The probability that at least 1 out of 9 cheeses chosen at random will be raw-milk would be the complement of no cheeses being raw milk. This means all 9 would be pasteurized; we know this probability to be 23.16%. This means the complement would be
1-0.2316 = 0.7684 = 76.84%.
1 out of 9 cheeses being raw-milk is 1/9 = 0.1111 = 11.11%.
85% of cheese are pasteurized; this means that 100-85 = 15% of cheeses are raw-milk. Thus an 11% probability would not be unusual.