Answer: a) Required minimum sample size= 219
b) Required minimum sample size= 271
Step-by-step explanation:
As per given , we have
Margin of error : E= 5% =0.05
Critical z-value for 90% confidence interval : 
a) Prior estimate of true proportion: p=28%=0.28
Formula to find the sample size :-

Required minimum sample size= 219
b) If no estimate of true proportion is given , then we assume p= 0.5
Formula to find the sample size :-

Required minimum sample size= 271
Answer:
The answer is C
Step-by-step explanation:
Just calculate it
22° you just subtract the numbers.
Answer:
7..the way you worded the options was confusing
Ratio is 7:9
add the ratio it becomes 16
272 members divided by 16
that makes it 17 per one ratio
women ratio is 9
17x9 is 153
i=153 women in the sports club
same thing with ii except it’s divided by 7
91/7 is 13
which means 13 per ratio
there are 9 ratios of women
9x13=117
ii=117 women in a sports club with 91 men with a ratio of 7:9