Answer:
(53.812 ; 58.188) ; 156
Step-by-step explanation:
Given that :
Sample size (n) = 51
Mean (m) = 56
Standard deviation (σ) = 9.5
α = 90%
Using the relation :
Confidence interval = mean ± Error
Error = Zcritical * (standard deviation / sqrt (n))
Zcritical at 90% = 1.645
Error = 1.645 * (9.5 / sqrt(51))
Error = 1.645 * 1.3302660
Error = 2.1882877
Hence,
Confidence interval :
Lower boundary = 56 - 2.1882877 = 53.8117123
Upper boundary = 56 + 2.1882877 = 58.1882877
Confidence interval = (53.812 ; 58.188)
2.)
Margin of Error (ME) = 1.25
α = 90%
Sample size = ((Zcritical * σ) / ME)^2
Zcritical at 90% = 1.645
Sample size = ((1.645 * 9.5) / 1.25)^2
Sample size = (15.6275 / 1.25)^2
Sample size = 12.502^2 = 156.3000
Sample size = 156
Answer:
1.49 x
hours
Step-by-step explanation:
1 day=24hours
1 year=365 days
365days=24 x 365=8760hours
17 years
= 8760hours x 17
=148920hours
=1.4892 x
= 1.49 x
hours
A) it is left skewed
B) the median is 5
C) the mean is 5.15
D) the mean would be more affected (a change of 1.05 versus a change of 0.5).
The majority of the data is to the right of the graph; this means it is left skewed.
To find the median, write all of the data values out:
2, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7
The middle value is 5.
We find the sum of this set of values and divide by 13, the number of data points, to find the mean:
2+3+4+4+5+5+5+6+6+6+7+7+7 = 67/13 = 5.15
If we added an additional data value at 20, the new median would be 5.5. The new mean would be (67+20)/14 = 6.2. The mean changes more than the median.
X= 9 1/4 or 9.25 in decimal form
Answer:
2%, 0.2, 1/2
Step-by-step explanation:
0.2 = 0.20 = 20%
1/2 = 0.50 = 50%
2% = 0.02