Answer:
2
Step-by-step explanation:
Answer:
(b)
Since we don't have prior estimation for the population proportion we can use the value
. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=54
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
Solution to the problem
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by
and
. And the critical value would be given by:
The margin of error for the proportion interval is given by this formula:
(a)
And on this case we have that
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
Since we don't have prior estimation for the population proportion we can use the value
. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=54
Answer:
K= 16.5 gallons per minute
Step-by-step explanation:
Time t (minutes) Water g (gallons)
For t= 1, g= 16.50,
for t= 1.5 ,g= 24.75
For t= 2,g= 33
Let the function be
Gallons g= k(time t)
Where k is the constant of proportionality
16.5= k(1)for when t= 1
24.75= k(1.5) ..for when t= 1.5
Solving gives
8.25=k(0.5)
8.25/0.5= k.
16.5 = k
K= 16.5 gallons per minute
Answer:
$70.34
Step-by-step explanation:
The total before the coupon and tax is:
$54.99 + $21.99 = $76.98
Now apply the 15% coupon:
Since the total price is 100% of the price, when you apply a 15% coupon, you pay 100% - 15% = 85% of the price. We need to find 85% of $76.98
85% * $76.98 =
= 0.85 * $76.98
= $65.43
The price after the 15% coupon, but before the tax, is $65.43
Now the total $65.43 is considered 100% of the price. The tax is 7.5%.
100% + 7.5% = 107.5%
Now we find 107.5% of $65.43
107.5% of $65.43 =
= 1.075 * $65.43
= $70.34
Answer: $70.34
Answer:
33
Step-by-step explanation: