Answer:
The 95% confidence interval based on this sample is =
[6.41, 7.79]
Step-by-step explanation:
The formula for Confidence Interval =
Mean ± z × standard deviation/√n
Sample mean = 7.1 hours
Standard deviation = 5 hours
n = 200 students
z = 95% confidence interval z score
= 1.96
C.I = 7.1 ± 1.96 × 5/√200
C.I = 7.1 ± 0.693
Hence, Confidence Interval
= 7.1 - 0.693
= 6.407
Approximately = 6.41
= 7.1 + 0.693
= 7.793
Approximately = 7.79
Therefore, the 95% confidence interval based on this sample is
[6.41, 7.79]
We are given :

Step 1: factor the part inside square root
The function given inside square root is of quadratic form.
So let us try to factorise it using AC method.
Here A*C = 4*25 = 100
so we have to find factors of 100 that add up to give -20.
the two factors are -10 and -10.
Rewriting the function :

=
=
=
Step 2:
Now we take square root of the factorised form

= 
Answer : (2x-5)
Look at it on the Internet
Answer:
2
Step-by-step explanation:
where both lines intersect
therefore 2 and 5 are the two solutions
Answer:
the answer would be 217 [degrees]
Step-by-step explanation:
Since m<1 and m<2 are next to each other, they are adjacent. Adjacent angles must share a common side which is m<W. This means they have to be added. m<1+m<2= m<XYZ
145+72=217