Answer:
If the lifetime of batteries in the packet is 40.83 hours or more then, it exceeds for 5% of all packages.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 15
Standard Deviation, σ = 1
Sample size = 4
Total lifetime of 4 batteries = 40 hours
We are given that the distribution of lifetime is a bell shaped distribution that is a normal distribution.
Formula:

Standard error due to sampling:

We have to find the value of x such that the probability is 0.05
P(X > x) = 0.05
Calculation the value from standard normal z table, we have,
Hence, if the lifetime of batteries in the packet is 40.83 hours or more then, it exceeds for 5% of all packages.
Answer:

Step-by-step explanation:
Given

Required
Ratio of odd numbers to total
First, list out the odd numbers

The card has 4 odd numbers out of a total of 6.
So, the ratio is:


Divide by 2

<em>Hence, the ratio of odd to total is 2 to 3</em>
Answer:
50
Step-by-step explanation:
Figure out all variables
100/(2x5= 10)-9+(3x.33=1)
100/10-9+1
100/2
50