Answer:
.b. It is one‐half as large as when n = 100.
Step-by-step explanation:
Given that a simple random sample of 100 batteries is selected from a process that produces batteries with a mean lifetime of 32 hours and a standard deviation of 3 hours.
i.e. s = 0.3
we obtain se of sample by dividing std devitation by the square root of sample size
i.e. s= 
when n =100 this = 0.3 and
when n =400 this equals 0.15
We find that when sample size is four times as large as original, std deviation becomes 1/2 of the original
Correction option is
.b. It is one‐half as large as when n = 100.
Question has missing details (Full question below)
Measurement error that is continuous and uniformly distributed from –3 to +3 millivolts is added to a circuit’s true voltage. Then the measurement is rounded to the nearest millivolt so that it becomes discrete. Suppose that the true voltage is 219 millivolts. What is the mean and variance of the measured voltage
Answer:
Mean = 219
Variance = 4
Step-by-step explanation:
Given
Let X be a random variable measurement error.
X has a discrete uniform distribution as follows
a = 219 - 3 = 216
b = 219 + 3 = 222
Mean or Expected value is calculated as follows;
E(x) = ½(216+222)
E(x) = ½ * 438
E(x) = 219
Variance is calculated as follows;
Var(x) = ((b-a+1)²-1)/12
Var(x) = ((222-216+1)²-1)/12
Var(x) = (7²-1)/12
Var(x) = 48/12
Var(x) = 4
Answer:
v=6
v=−4
Step-by-step explanation:
Hi!
Shawna is correct because since it's multiplied to the 5-n you have to do the opposite which is division.
Dexter is also correct because after distributing you can continue solving, there is nothing wrong with that.
Hope this helps!
