Answer:
median = 17.5
Step-by-step explanation:
The median is the middle value of a data set arranged in ascending order. If there is not a middle value then the median is the average value of the numbers either side of the middle.
Data in ascending order is
8, 15, 17, 18, 19, 21
The median is between 17 and 18, hence
median = 
= 17.5
Answer:
A and D
Step-by-step explanation:
67 right out of 100 for the fraction and 67/100 = 67%
Answer:
see explanation
Step-by-step explanation:
Using De Moivre's theorem
Given
[ 4(cos15° + isin15° ) ]³, then
= 4³ [ cos(3 × 15°) + isin(3 × 15°) ]
= 64 (cos45° + isin45° )
= 64 (
+ i )
= 64 ( (1 + i) )
= 32
(1 + i)
= 32 + 32 i
A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
