Answer:
We have to find the 90% confidence interval for the mean
Given sample size
Sample mean
Population standard deviation
Here the confidence level is 90% then
And
The 90% confidence interval is
Here is the critical value at 0.05
From the tables
Now the 90% confidence interval is =
=
=(3840.44, 4133.56)
Hence the 90% confidence interval for the mean is (3840.44, 4133.56)
Answer:
8 pounds of peanuts, 6 pounds of raisins and 6 pounds of chocolate chips
Step-by-step explanation:
Let x be the number of pounds of peanuts and y be the number of pounds of raisins and chocolate chips.
Peanuts cost $2 per pound, then x pounds cost $2x.
Raisins cost $2.50 per pound, then y pounds cost $2.50y.
Chocolate chips cost $4 per pound, then y pounds cost $4y.
In total, x+y+y=20 and those 20 pounds cost
2x+2.50y+4y=20·2.75.
Solve the system of two equations:
![\left \{ {{x+2y=20} \\ \\ \\ \\ \\ \\ \atop {2x+6.5y=55}} \right.](https://tex.z-dn.net/?f=%5Cleft%20%5C%7B%20%7B%7Bx%2B2y%3D20%7D%20%5C%5C%20%5C%5C%20%5C%5C%20%5C%5C%20%5C%5C%20%5C%5C%20%5Catop%20%7B2x%2B6.5y%3D55%7D%7D%20%5Cright.)
From the first equation:
![x=20-2y](https://tex.z-dn.net/?f=x%3D20-2y)
Substitute x into the second equation:
![2(20-2y)+6.5y=55\\ \\40-4y+6.5y=55\\ \\2.5y=15\\ \\25y=150\\ \\y=6\\ \\x=20-2\cdot 6=8](https://tex.z-dn.net/?f=2%2820-2y%29%2B6.5y%3D55%5C%5C%20%5C%5C40-4y%2B6.5y%3D55%5C%5C%20%5C%5C2.5y%3D15%5C%5C%20%5C%5C25y%3D150%5C%5C%20%5C%5Cy%3D6%5C%5C%20%5C%5Cx%3D20-2%5Ccdot%206%3D8)
Answer:
idk what this is 4
Step-by-step explanation:
Answer:
12 and 16 or 12:16
6 x 2 = 12
8 x 2 =16
12 + 16 = 28
Step-by-step explanation:
Answer:
7 miles
Step-by-step explanation:
As, we will take unit rate as "x"
So, for one day = x distance
For 5 days = 5(x)
For 5 days she covered 35 miles
So therefore,
5(x) = 35 miles
X= 35/5
X=7 miles
For a day= 7 miles are covered