Given:
Sample mean = 65.4
Standard deviation = 1.2
Sample size = 45
Confidence level = 99%
To find:
The confidence interval.
Solution:
The formula for confidence interval is

where,
is sample mean, z* is confidence value, s is standard deviation and n is sample size.
Confidence value or z-value at 99% = 2.58
Putting the given in the above formula, we get




Therefore, the correct option is D.
To factor a quadratic of the form ax^2+bx+c you need to find two values, j and k, which satisfy two conditions...
jk=ac=12 and j+k=b=8, so j and k must be 2 and 6
Then the factors are just (a+j)(a+k), in this case:
(a+2)(a+6)
So the missing term was 6
1000 meters make 1km. So let's compare that with the question.
1000m=1km
Y=33km
I represented the unknown with Y. Next, you have to cross and multiply. 33 will multiply 1,000 to give 33,000. And Y will multiply 1 to give Y. That will be;
Y=33,000m
33km makes 33,000m.
Hope that helped. Have a nice day
To find decimal, divide 13/50= 0.26
To find percent divide decimal above by 100 (or move decimal place to the right two places).
0.26/100= 26%
Hope this helps! :)
___________________________
◆ AREA RELATED TO CIRCLES ◆ ___________________________
As shown in the figure ,
Radius of circle = 5 cm
Side of square = 2 × (Radius of inscribed circle)
Side of square = 2 × 5 cm
Side of square = 10 cm = a
___________________________
Now ,
Area of shaded region = (Area of square) - ( Area of inscribed circle )
Area of shaded region =

Area of shaded region =

Area of shaded region = 100 - 78.571