Answer:
Step-by-step explanation:
Given is a function f in two variables as

To find critical points of the given function and also to find max, min or saddle point.
Find the partial derivatives



Equate first derivatives to 0
Adding fx and fy we get

x=±y
Only real roots are (x,y) =(3,3) and (-3,-3)

(3,3) is a saddle point

(-3,-3) is also a saddle point.
23.535 = 23 353/1000 = 23 107/200
Answer:

Step-by-step explanation:
Required
The population standard deviation
First, calculate the population mean

This gives:



The population standard deviation is:

So, we have:




Answer: 20 students
Step-by-step explanation:
i beieve this is the answer dont be mad if its not
Answer:
Two students will take 24 minutes to wash the car.
Step-by-step explanation:
In this case we can apply a rule of three to find out the time that will take for the students to wash the car. This has to be done such as:
3 students -> 16 minutes
2 students -> x minutes
3/2 = 16/x
But in this cases the problem states that this variables are inversely proportionate, which means that if there's less students washing the car they will take more time to finish the job. So we need to invert one of the fractions before computing the result.
3/2 = x/16
2*x = 3*16
x = 48/2 = 24 minutes.
Two students will take 24 minutes to wash the car.