9514 1404 393
Answer:
after 7 minutes
19,600 feet
Step-by-step explanation:
Here's the "pencil and paper" solution:
The two altitude equations are ...
y = 41300 -3100x
y = 2800x
They can be solved by setting the expressions for y equal to each other.
2800x = 41300 -3100x
5900x = 41300
x = 41300/5900 = 7
y = 2800·7 = 19600
The planes will both be at 19,600 feet after 7 minutes.
r - radius, h - height
The diameter is twice the radius.
The answer is c. 791.3 m³.
Answer:
We have strong evidence that on average, students study less than 150 minutes per night during the school week
Step-by-step explanation:
Normal distribution:
mean μ₀ = 150
Sample:
Sample size n = 272
Sample mean x = 141
Sample standard deviation s = 66
The standard error of the sample mean SE = σ /√n
SE = 66/√272
SE = 66 / 16,49
SE = 4
Test Hypothesis:
Null hypothesis H₀ x = μ₀
Alternative hypothesis Hₐ x < μ₀
z(s) test statistics is:
z(s) = ( x - μ₀ ) / s/√n
z(s) = - 9 /4
z(s) = - 2,25
p-value for that z(s) p-value = 0,0122
Then for α = 0,05 p-value < 0,05
We are in the rejection region we need to reject H₀
