Answer:
a = -5
Step-by-step explanation:
0.044 as a fraction is 44/1000
Simplified is 11/250
So your answer is 11/250
Hope I Helped You!!!
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
Part A
Use the binomial probability distribution formula.
p = 0.54 = probability of getting a purple marble
n = 5 = sample size
x = 2 = number of purple we want to get

The
portion is from the nCr combination formula. The exclamation marks indicate a factorial.
Alternatively, you could use Pascal's Triangle for that portion.
<h3>Answer: 0.283831776</h3>
This decimal value is exact. Round it however you need to.
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Part B
To find the expected value, aka the mean, we multiply the sample size and probability of getting a purple marble on any single selection.
n*p = 5*0.54 = 2.7
<h3>Answer: 2.7</h3>