What term describes this polygon ?

At the Foremost State Bank the average savings account balance in 2012 was $1900. A random sample of 45 savings account balanes

lakkis [162]

Answer:

The calculated |t| = |-26.517|=26.517 > 2.326 at 0.01 level of significance

Null hypothesis is rejected at 0.01 level of significance

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

Step-by-step explanation:

Step(i):-

Mean of the Population = 1900

Given random sample size 'n' = 45

Mean of the sample x⁻ = 1000

Standard deviation of the sample = 225

Null Hypothesis:-

There is no difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012.

Alternative Hypothesis :-

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

Step(ii):-

Test statistic

$t = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }$

$t = \frac{1000-1900 }{\frac{225}{\sqrt{45} } }$

t = -900 /33.54 = -26.517

|t| = |-26.517|=26.517

Degrees of freedom

γ = n-1 = 45-1 =44

t₍₀.₀₁ , ₄₄₎ = 2.326

The calculated |t| = |-26.517|=26.517 > 2.326 at 0.01 level of significance

Null hypothesis is rejected at 0.01 level of significance

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

4 0

3 years ago

Please help fast!!!!

emmasim [6.3K]

I think it’s 3 not sure!

7 0

2 years ago

The world population is estimated to be 7.8 billion in 2020, and growing at an instantaneous rate of 1.05%. (a) Estimate the pop

REY [17]

Answer:

Population in 2100 is 17.99 billion.

Step-by-step explanation:

The population of the world in 2020 = 7.8 billion.

The growth rate = 1.05%

Now find the population after 2100. Use the below formula to find the population.

Population in 2100 = Population of 2020 (1 + growth rate)^n

Population in 2100 = 7.8 (1 + 0.0105)^80

Population in 2100 = 17.99 billions.

Now, find the growth rate in 2100.

dN/dt = [r N (K – N) ] / K

r = Malthusian parameter

K = carrying capacity.

Now divide both sides by K, now x = N/K then do the differential equation.

dx/dt = r x ( 1- x)

Now integrate, x(t) = 1/ [ 1 + (1/x – 1) c^-rt

From the first equation = dN/dt = (13 – 7.8) / 80 = (r × 7.8×(13 – 7.8) / 12

0.065 = (r × 7.8× 5.2) / 12

0.065 = r × 3.38

r = 1.92%

3 0

3 years ago

Please help. It’s a multiple choice question. I’ve my answer, but I’m not sure.

S_A_V [24]

Answer:

66 degree

Step-by-step explanation:

given:

angle FAB = 48 degree

angle ECB = 18 degree

in triangle HBC , angle H is also 48 degree degree since the line is parallel the connection between angle H and angle A is alternate interior angle and alternate interior angle are always equal.

so angle H = 48 degree

in triangle HBC

angle H + angle C = angle ABC (sum of two interior opposite angles are equal to the exterior angle formed)

48 + 18 = angle ABC

66 = angle ABC

3 0

3 years ago

The angle of elevation to the top of a 30 story skyscraper is measured to be 3 degrees from a point on the ground 2,000 feet fro

Leto [7]

You have an angle of elevation of 3 degrees and you're 2000 ft from base of 30 story building.
Draw a picture of this. Then tan(3) = ht of bldg/2000 
I get a height of 104.82 ft rounded to 2 dp. 

5. Ok. use the Pythagorean Theorem here to find the hypotenuse of the right triangle 
hypt = sqrt(50^2 + 9^2) 
Now sine of the angle of elevation is 50/hypt. = 0.984 or 0.98 to 2 dp.

4 0

3 years ago