Answer:
98% confidence interval is (-0.105 , 0.265)
Step-by-step explanation:
n1 = 75 n2 = 75
X1 = 48 X2 = 42
P1 = X1/N1 = 0.64 P2 = X2/N2 = 0.56
98% confidence interval for difference between two proportions is :
P1 - P2 <u>+</u> Z 
= 0.08 <u>+</u> 0.185
= (-0.105 , 0.265)
98% confidence interval is (-0.105 , 0.265)
Answer: P = 0.75
Step-by-step explanation:
Hi!
The sample space of this problems is the set of all the possible sales. It is divided in the disjoint sets:

We have also the set of sales of boat accesories
, the colored one in the image.
We are given the data:

From these relations you can compute the probabilities of the intersections colored in the image:

You are asked about the conditional probability:

To calculate this, you need
. In the image you can see that the set
is the union of the two disjoint pink and blue sets. Then:

Finally:
