Answer:
A sample of 179 is needed.
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 
.
That is z with a pvalue of 
, so Z = 1.44.
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.
A previous study found that for an average family the variance is 1.69 gallon?
This means that 
If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?
A sample of n is needed, and n is found for M = 0.14. So
Rounding up
A sample of 179 is needed.
Answer:
= 6.5
Step-by-step explanation:
You have to plug in 1.5 for x
->
4(1.5) + 0.5 = 6.5
Ok, so first we distribute, you multiply the seven into everything in the parentheses next to it. So far we have, 14a+21+3(4a-2). You distribute the three into the parentheses to get, 14a+21+12a-6. You combine the like terms to get, 26a-15. You cannot simplify it any further so the answer is 26a-15.
Answer:
SAS
Step-by-step explanation:
There is one common side (S)
both the triangles have 90° common (A)
Opposite sides are equal which is given (S)
They both are right angled triangles
Answer:
1. yes 2. no
Step-by-step explanation:
