Answer:
A. 9.7%
Step-by-step explanation:
margin of error:
z *
n is sample size
z is the z score (for a 95% confidence interval you would use 1.96)
p is the sample proportion
to solve for 'p', remember that if a decimal value is given, use that. but if it is a whole number, then divide that number by the sample size, and substitute it into the formula.
in this case we are given 43% so 0.43.
in the formula :
1.96 *
if you calculate this you get around 0.09703 this is 9.7%
Answer:
a) 20<h≤30.
b) 26.17 hrs
Step-by-step explanation:
The missing table is shown in attachment.
Part a)
We need to find the class interval that contains the median.
The total frequency is
The median class corresponds to half
That is the 15th value.
We start adding the frequency from the top obtain the least cumulative frequency greater or equal to 15.
2+8+9=19
This corresponds to the class interval 20<h≤30.
Adding from the bottom also gives the same result.
Therefore the median class is 20<h≤30.
b) Since this is a grouped data we use the midpoint to represent the class.
The median is given by :
