Answer:
<u>553.143 mi²</u>
Step-by-step explanation:
Surface Area (Cylinder) :
- 2πr (r + h)
- 2 x 22/7 x 8 (8 + 3)
- 16 x 22/7 x 11
- 176 x 22/7
- 3872/7
- <u>553.143 mi²</u>
<span>Length of outer track = sum of length of 10 pieces = circumference of the outer circle
if R is the Radius of outer circle then...
Circumference of the outer track = 2pi*R
Similarly the circumference of the inner track (with radius r) = 2pi*r
length of each outer piece is 3.4 inch more than length of inner piece
So total outer length is 10*3.4 =34 inches more than the inner length.
=> Outer Circumference - Inner Circumference = 34 inches
=> 2pi*R - 2pi*r = 34
=> 2pi(R -r) = 34
=> R-r = 34/2pi = 5.41 inches
=> R-r = Width of the track = 5.41 inches</span>
Answer:
The 95% confidence interval for the true proportion of university students who use laptop in class to take notes is (0.2839, 0.4161).
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for population proportion <em>P</em> is:

The information provided is:
<em>x</em> = number of students who responded as"yes" = 70
<em>n</em> = sample size = 200
Confidence level = 95%
The formula to compute the sample proportion is:

The R codes for the construction of the 95% confidence interval is:
> x=70
> n=200
> p=x/n
> p
[1] 0.35
> s=sqrt((p*(1-p))/n)
> s
[1] 0.03372684
> E=qnorm(0.975)*s
> lower=p-E
> upper=p+E
> lower
[1] 0.2838966
> upper
[1] 0.4161034
Thus, the 95% confidence interval for the true proportion of university students who use laptop in class to take notes is (0.2839, 0.4161).
Answer:
the answer is 300
Step-by-step explanation:
9x - 27 < 4x + 40
-> 5x < 67
-> x < 67/5