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
In an isosceles triangle, two sides are equal to each other. So, we know that the third side is either 6 or 15 inches.
If the third side is 6 inches, it would not make a triangle. The sum of any to sides of a triangle must be larger than the third side. However, 6+6 is LESS than 15, so 6 inches would not be the answer.
By process of elimination, the third side is 15 inches. Good luck!
Answer:
462.5 pages
Step-by-step explanation:
You find out how many books she reads in 1 day then you can multiply it by 5 to get 5 days.
If she reads 185 in 2 days. Divide 185 by 2 to get 1 day.
185/2 = 92.5 pages
Now multiply 92.5 by 5 to get how many pages she read after 5 days.
92.5 x 5 = 462.5 pages
Answer:
A = 40°
B = 50°
Step-by-step explanation:
If cos A = sin B, then A + B = 90
So, 2x/3 + 20 + 2x - 10 = 90
2x + 60 + 6x - 30 = 270
8x + 30 = 270
8x = 240
x = 30
2x/3 + 20 = 60/3 + 20 = 20 + 20 = 40
2x - 10 = 2(30) - 10 = 60 - 10 = 50 or 90 - 40 = 50
Brandon is not correct because he should have added 6 negative unit tiles to isolate the variable in step 2—— the answer would have been x=-1
