Answer:
1200
Step-by-step explanation:
The number who drink coffee is 3/4 of 8000, so ...
... (3/4)×8000 = 6000.
Of those, 1/5 add cream, so the number of coffee drinkers who add cream to their coffee is ...
... (1/5)×6000 = 1200.
_____
<em>Alternate solutions</em>
We have computed ...
... (1/5)×((3/4)×8000) = 1200
Since multiplication is associative, you can multiply the fractions first, if you wish:
... ((1/5)×(3/4))×8000 = (3/20)×8000
... = 24000/20 = 1200
or
... = 3×(8000/20) = 3×400 = 1200
First, let's expand the right side. Now our equation is
Now, we gather all the terms with x in it on the left side, and the numbers without x on the right. We get:
And then we can make this
We divide both sides by 12 to get x on its own, so x = 13/12 or 1.08
Answer:
12
Step-by-step explanation:
in this problem there is A+b=15
A=9
B=12
Answer:
a) Margin of error = 166.311
b) sample size ≥ 62
Step-by-step explanation:
Given:
Average cost = $1599
Sample size = 50 persons
Standard deviation = $600
Confidence level is 95%
a) Margin of error =
Now for confidence level of 95% z-value = 1.96
Thus,
Margin of error =
or
Margin of error = 166.311
b) For Margin of error ≤ 150
≤ 150
or
≤ 150
or
≤ √n
or
√n ≥ 7.84
or
n ≥ 61.4656
Therefore,
sample size ≥ 62