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:
2x-12
Step-by-step explanation:
First you distribute the -2 to the x and +3
this will make you expression be:
4x-6-2x-6
you then do -6+-6
this will make your expression be:
4x-12-2x
After you get this you have to combine like terms. the like terms in the expression are the two with x being you variable. 4x and -2x.
Once you have combined like terms your solution should be:
2x-12
Answer:
3874.5342
Step-by-step explanation:
9.63 divide by 100 = 0.0963
0.0963x40 234= 3874.5342