The equation of a parabola with vertex at (h,k) is
y=a(x-h)²+k
vertex isi at (0,0)
y=a(x-0)²+0
y=a(x)²
y=ax²
find a
we see that one point is (14,-74)
x=14 and y=-74
-74=a(14²)
-74=196a
divide both sides by 196
-37/98=a
the equation is
Answer:
24 terms
Step-by-step explanation:
The sum of an arithmetic sequence is the average of the first and last terms, multiplied by the number of terms. The last term is given by ...
an = a1 + (n-1)d
We have a sequence with first term a1 = 2 and common difference d = 2. So the last term is ...
an = 2+ 2(n -1) = 2n
Then the average of first and last terms times the number of terms is ...
Sn = 600 = n(2 + 2n)/2 = n(n+1) . . . . . . close to n²
We can solve the quadratic in n, or we can estimate the value of n as the integer just below the square root of 600.
√600 ≈ 24.5
so we believe n = 24.
_____
<em>Check</em>
S24 = 24·25 = 600 . . . . . . as required.
Answer:
His 95% confidence interval is (0.065, 0.155).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
His 95% confidence interval is (0.065, 0.155).
I believe it's -5.25 because it's adding .50 everytime
