Answer:
The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 24 - 1 = 23
98% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 23 degrees of freedom(y-axis) and a confidence level of
. So we have T = 2.5
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 42 - 1.02 = $40.98.
The upper end of the interval is the sample mean added to M. So it is 42 + 1.02 = $43.02.
The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.
Call n, the first of those consecutive terms, then three consecutive terms are:n, n +1, and n +2.
So, the equation will be n + (n +1) + (n +2) = 467
=> n + n + 1 + n + 2 = 467
=> 3n + 3 = 467
All of them are valid forms of the equation for the sum of three consecutive integers is 467.
You can solve it now, if you want:
3n = 467 - 3
3n = 464
n = 464 / 3
n = 154.6
The solution means that there are not three consecutive numbers whose sume is 467.
You can verifiy that if you take 154 + 155 + 156 = 465
And 155 + 156 + 157 = 468
Answer:
D. 4.5%.
Step-by-step explanation:
Interest earned in 6 months = 572.6 - 560 = $12.60.
As a percentage this is (12.60 * 100) / 560
= $ 2.25%.
So the annual interest is 2 * 2.25
= 4.5%.
Are you asking how to solve this equation?
2√20=2((√4)(√5)=2((2)(√5)=4√5
now we have
4√5-3√5=1√5=√5