We need to find out how many adults must the brand manager survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage.
From the given data we know that our confidence level is 90%. From Standard Normal Table we know that the critical level at 90% confidence level is 1.645. In other words, 
.
We also know that E=5% or E=0.05
Also, since, 
is not given, we will assume that =0.5. This is because, the formula that we use will have 
in the expression and that will be maximum only when =0.5. (For any other value of , we will get a value less than 0.25. For example if, is 0.4, then 
and thus, 
.).
We will now use the formula
We will now substitute all the data that we have and we will get
which can approximated to n=271.
So, the brand manager needs a sample size of 271
Answer:
r=7
Step-by-step explanation:
74000=28000(1+r/12)^12(14)
divide 74000 by 28000, and cancel out 28000.
1.00580=1+r/12
(100) .06962=r
r = 6.96198
the 6 after the 9 rounds 9 to 0, which rounds the 6 to 7
r=7
Step-by-step explanation:
You can see the full detailed explanation in the attached files
Answer:
a= Apple = 3
b= Banana =5
v= Lollypop=1
Step-by-step explanation:
36 is divided into 2 giving us 18
Let apple=a
Banana=b
Lollypop=c
In the first half
An apple + 3 bananas=18
a+3b=18 (1)
Second half is further divided into 2
That is,
18÷2=9
First half of the second half
3apples=9
3a=9 (2)
Second half of the second half
1 apple + 1 banana + 1 lollypop=9
a+b+c=9 (3)
a+3b=18 (1)
3a=9 (2)
a+b+c=9 (3)
From (2)
3a=9
Divide both sides by 3
a=9/3
a=3
Substitute a=3 into 1
a+3b=18
3+3b=18
3b=18-3
3b=15
Divide both sides by 3
b=15/3
=5
b=5
Substitute the value of a and b into (3)
a+b+c=9
3+5+c=9
8+c=9
c=9-8
c=1
Therefore,
a= Apple = 3
b= Banana =5
v= Lollypop=1
