Answer:
(
−
3
,
∞
)
Step-by-step explanation:
Answer: It will take 4.4 hours to fill the pool.
Step-by-step explanation: One pump can fill a swimming pool in 8 hours and another pump can fill it in 10 hours. If both pumps are opened at the same time, how many hours will it take to fill the pool?
Aprox. 4.4 hours.
Hope this Helps!
To find the average speed she goes in one mile, simply divide 21 by 4, this gives you 5.25.
To get the answer for part B, divide 42 by 5.25, Wich gives you 8. You can always check your work by doing the opposite as you did to solve, so 8 x 5.25 should equal 42, which it does.
Answer:
(a) 100
(b) 10.27
Step-by-step explanation:
We are given
No of elements = 15
Σ(x-c) = 72,Σ(x-c)^2 = 499.6
,where c is a constant
and the sample mean is 104.8.
(a) lets take into account Σ(x-c) = 72
this means that we have the sum of the 15 elements of x and each element of x is subtracted by the constant c
so the equation becomes Σxi -15c = 72, ............(1)
where xi means the sum of the elements of x from 1 to 15.
we are given the mean as 104.8
this means that Σxi/15 = 104.8
Σxi = 15*104.8 = 1572 .............(2)
substituting (2) in (1)
we get
1572 - 15c = 72
15c = 1500
c = 100
(b) We will use the property that variance does not change when a constant value is added or subtracted to the elements. This we can observe in the given equation that c is a constant that has the value of 100.
so the variance is
σ^2 = Σ(x-c)^2/15 - (Σ(x-c)/15 )^2
= 499.6/15 - (72/15)^2
= 33.31 - 23.04
σ^2 = 10.27
Therefore the variance of the given problem is 10.27.
Square feet! Cubic feet are used for 3D spaces, or volume, which won't be necessary for a 2D surface. Yards are commonly used for distance and perimeter. Square yards would be much too long for something such as tiling on a bathroom floor. Hope this helps.