simplify exponent: 20*(9-4)/50
simplify parentheses: 20*5/50
multiply: 100/50
divide: 2
Answer is 72
Step by step
Using order of math rules of PEMDAS, we do the inner parentheses “P” first, working outwards with parentheses and then exponents, multiply and divide, add and subtract.
2x [4x(2+1)x3] add inner parentheses
2 x [4 x 3 x 3] multiply inside brackets
2 x 36 multiply for your answer
= 72
Answer:
The 95% confidence interval is

Step-by-step explanation:
From the question we are told that
The first sample size is 
The first sample mean is
The first standard deviation is 
The second sample size is 
The second sample mean is 
The second standard deviation is 
Generally the degree of freedom is mathematically represented as
![df = \frac{ [ \frac{s_1^2 }{n_1 } + \frac{s_2^2 }{n_2} ]^2 }{ \frac{1}{(n_1 - 1 )} [ \frac{s_1^2}{n_1} ]^2 + \frac{1}{(n_2 - 1 )} [ \frac{s_2^2}{n_2} ]^2 }](https://tex.z-dn.net/?f=df%20%3D%20%20%5Cfrac%7B%20%5B%20%5Cfrac%7Bs_1%5E2%20%7D%7Bn_1%20%7D%20%20%2B%20%5Cfrac%7Bs_2%5E2%20%7D%7Bn_2%7D%20%5D%5E2%20%7D%7B%20%5Cfrac%7B1%7D%7B%28n_1%20-%201%20%29%7D%20%5B%20%5Cfrac%7Bs_1%5E2%7D%7Bn_1%7D%20%5D%5E2%20%2B%20%5Cfrac%7B1%7D%7B%28n_2%20-%201%20%29%7D%20%5B%20%5Cfrac%7Bs_2%5E2%7D%7Bn_2%7D%20%5D%5E2%20%20%7D)
=> ![df = \frac{ [ \frac{5.9^2 }{34 } + \frac{4.4^2 }{34} ]^2 }{ \frac{1}{(34 - 1 )} [ \frac{5.9^2}{34} ]^2 + \frac{1}{(34- 1 )} [ \frac{4.4^2}{ 34} ]^2 }](https://tex.z-dn.net/?f=df%20%3D%20%20%5Cfrac%7B%20%5B%20%5Cfrac%7B5.9%5E2%20%7D%7B34%20%7D%20%20%2B%20%5Cfrac%7B4.4%5E2%20%7D%7B34%7D%20%5D%5E2%20%7D%7B%20%5Cfrac%7B1%7D%7B%2834%20-%201%20%29%7D%20%5B%20%5Cfrac%7B5.9%5E2%7D%7B34%7D%20%5D%5E2%20%2B%20%5Cfrac%7B1%7D%7B%2834-%201%20%29%7D%20%5B%20%5Cfrac%7B4.4%5E2%7D%7B%2034%7D%20%5D%5E2%20%20%7D)
=> 
Generally the standard error is mathematically represented as

=> 
=> 
From the question we are told the confidence level is 95% , hence the level of significance is

=> 
Generally from the t distribution table the critical value of at a degree of freedom of is

Generally the margin of error is mathematically represented as

=> 
=> 
Generally 95% confidence interval is mathematically represented as

=> 
=> 
Someone is answering good luck