The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
10 hours was the full time she painted
The point of intersection is the point where lines intersect.
<em>There will be 595 intersections for 35 lines, where no 3 lines are concurrent.</em>
<em />
Given
<em />
<em> --- the number of lines</em>
<em />
<em> --- no three lines are concurrent</em>
<em />
When no three line are concurrent, it means that no three lines meet at the same point.
<u>So, the sequence of intersection is:</u>
- <em>0 intersection for 1 line</em>
- <em>1 intersection for 2 lines</em>
- <em>3 intersections for 3 lines</em>
- <em>6 intersections for 4 lines</em>
<em />
Following the above sequence, the number of intersections for n lines is:

In this case, 
So, we have:




<em>Hence, there will be 595 intersections for 35 lines, where no 3 lines are concurrent.</em>
<em />
Read more about lines of intersections at:
brainly.com/question/22368617
Answer:
x²-7x=0
Step-by-step explanation:
please mark as brainliest
Answer:
4
Step-by-step explanation:
we know that 2/15 : 1/30 = 2/15 * 30 = 60/15 = 4