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:
Option D is the correct answer.
Explanation:
A girl has 3 different swimsuits, 4 different shorts and 3 different pairs of flip-flops.
Different ways can this girl wear a swimsuit, a pair of short and a pair of flip-flops = 3P₁ x 4P₁ x 3P₁
= 3 x 4 x 3
= 36
Different ways can this girl wear a swimsuit, a pair of short and a pair of flip-flops = 36
Option D is the correct answer.
Answer:
$225.50 (nearest cent)
Step-by-step explanation:
1 foot ≈ 0.3048 m
Width of room = 15 ft ≈ 15 x 0.3048 = 4.572 m
Length of room = 18 ft ≈ 18 x 0.3048 = 5.4864 m
Area of room = width x length = 4.572 x 5.4864 = 25.0938208... m²
Cost of carpet = $8.99 per m²
Total cost of carpet = 25.0938208 x 8.99 = $225.50 (nearest cent)
32,879 rounded to the nearest thousand is 33,000. It's because 32,879 is closer to 33,000 than to 32,000.
<span>I hope it will help you with rounding in the future :)</span>