Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-

Given : Sample size :
, which is a large sample , so we apply z-test .
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Now, a confidence interval at the 95% level of confidence will be :-

Interesting question about feet and inches. The best way to solve this problem is to ask yourself how many inches are in a foot. Since there are 12 inches in every foot then the length of 2'8" can be written as (2*12)" + 8". Which is 24+8 or 32 inches. The second number (1'6") can be written as (1*12)"+6" which is 18 inches. 32 + 18 = 50 inches. Or, if you want to change this back into feet and inches just divide it by 12. 50/12 is 4 R. 2. So 4'2".
Answer:
900 yards
Step-by-step explanation:
540/3=180
180x5=900
Answer:
2 7/12
Step-by-step explanation:
−512−−93=?
Since the the second fraction is negative and you are subtracting, remove the negative sign and switch the operation to addition.
The equivalent equation is
−512+93=?
The fractions have unlike denominators. First, find the Least Common Denominator and rewrite the fractions with the common denominator.
LCD(-5/12, 9/3) = 12
Multiply both the numerator and denominator of each fraction by the number that makes its denominator equal the LCD. This is basically multiplying each fraction by 1.
(−5/12×1/1)+(9/3×4/4)=?
Complete the multiplication and the equation becomes
−5/12+36/12=?
The two fractions now have like denominators so you can subtract the numerators.
Then:
−5+36/12=31/12
This fraction cannot be reduced.
The fraction
31/12
is the same as
31÷12
Convert to a mixed number using
long division for 31 ÷ 12 = 2R7, so
31/12=2 7/12
Therefore:
−5/12−−9/3=2 7/12