In this question, you're solving for a.
Solve for a:
-8(1 - a) =-7 -(1 - 3a)
<em>use the distributive property</em>
-8 + 8a = -7 -(1 - 3a)
-8 + 8a = -7 - 1 + 3a
<em>combine like terms</em>
-8 + 8a = -8 + 3a
<em>subtract 3a from both sides</em>
-8 + 5a = -8
<em>add 8 to both sides</em>
5a = 0
<em>divide both sides by 5</em>
a = 0
63 I think, you would subtract
Answer:
a.1.90 years
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
In this question:
So
So the correct answer is:
a.1.90 years
Answer:
440
Step-by-step explanation:
