72*12 = 2*2*2*2*2*3*3*3 = 2^5*3^3
The answer is C, hope this helps
Answer:
0.0323 = 3.23%. Is unusual
Step-by-step explanation:
Using the normal distribution we can find z value with the mean and standard deviation as follows. x is the value we want to know its probability
z = (x - mean)/standard deviation
z = (5-8.54)/1.91
z = -1.85
Using z tables for normal distribution, for z = 1.85, we have an area under the curve of 0.9677. Since we want to know the probability for 5 minutes or less, we have to substract from
p = 1- 0.9677
p = 0.0323
An event with a probability less than 5% is considered unusual.
