Answer:
The upper bound is 399.5
Step-by-step explanation:
Let's start by calculating the mean value of the distribution as the addition of all values given divided by 12:
Average = 289.75.
If the standard deviation is 56, then the upper bound in 95% the confidence interval for the mean price of the phones is going to be given by the mean value added to 56 times 1.96 (since 95% of the population is withing 1.96 times the standard deviation)
That is: 289.75 + 56 * 1.96 = 399.51
which rounded to one decimal place gives: 399.5
Answer:
Step-by-step explanation:
if you know that the perimeter is 20,
then you have to divide by 4 to get the length of one side
20/4=5.
Draw the diagonal and write in it's length as x.
Use Pythagorean formula
Then know that a2+b2=c2
and use the two side lengths as a and b.
This gives you the equation
5^2+5^2=x^2.
Do the calculations and solve the equation.
25+25=x^2
50=x^2
√50=x.
Therefore x=√50 where x equals the length of the diagonal.
Answer: B.

Step-by-step explanation:
Let's solve your system by elimination.
4x−2y=8;−2x+2y=6
Add these equations to eliminate y:
4x-2y=8
-2x+2y=6
2x=14
Substitute 7 for x in 4x−2y=8:
(4)(7)−2y=8
−2y+28=8 (Simplify both sides of the equation)
−2y+28+−28=8+−28 (Add -28 to both sides)
−2y=−20
−2y/−2=−20/−2 (Divide both sides by -2)
y=10
A. 12pi meters.
Circumference = pi x diameter (pi x 12 = 12pi)
Diameter = 2 x radius (2 x 6 = 12)