Given:
μ = 200 lb, the mean
σ = 25, the standard deviation
For the random variable x = 250 lb, the z-score is
z = (x-μ)/σ =(250 - 200)/25 = 2
From standard tables for the normal distribution, obtain
P(x < 250) = 0.977
Answer: 0.977
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Answer: $4,365.10
Step-by-step explanation:
Ok, we know that:
The account starts with $2350
There is a simple interest of 3.75% (or 0.035).
Then after one year, the amount in the account will increase by 3.75%, this means that the amount will be:
$2350 + 0.035*$2350 = (1.035)*$2350.
After another year, we have the same increase (but applied to the new amount in the account):
(1.035)*$2350 + 0.035*(1.035)*$2350. = (1.035)^2*$2350
And so on.
You already can see the pattern here, the amount of money in the saving account after N years will be:
M(N) = $2350*(1.035)^N.
Now we can answer:
what is the balance of the account if it earns a simple interest of 3.75% for 18 years?
Just replace N by 18 in that equation:
M(18) = $2350*(1.035)^18 = $4,365.10
Answer:
- There is no significant evidence that p1 is different than p2 at 0.01 significance level.
- 99% confidence interval for p1-p2 is -0.171 ±0.237 that is (−0.408, 0.066)
Step-by-step explanation:
Let p1 be the proportion of the common attribute in population1
And p2 be the proportion of the same common attribute in population2
: p1-p2=0
: p1-p2≠0
Test statistic can be found using the equation:
where
- p1 is the sample proportion of the common attribute in population1 (
)
- p2 is the sample proportion of the common attribute in population2 (
)
- p is the pool proportion of p1 and p2 (
)
- n1 is the sample size of the people from population1 (30)
- n2 is the sample size of the people from population2 (1900)
Then
≈ 2.03
p-value of the test statistic is 0.042>0.01, therefore we fail to reject the null hypothesis. There is no significant evidence that p1 is different than p2.
99% confidence interval estimate for p1-p2 can be calculated using the equation
p1-p2±
where
- z is the z-statistic for the 99% confidence (2.58)
Thus 99% confidence interval is
0.533-0.704±
≈ -0.171 ±0.237 that is (−0.408, 0.066)