Cos( 30 ) = 19√3 / x
√3 / 2 = 19√3 / x
Simplify √3 from both sides
1 / 2 = 19 / x
Multiply both sides by x
1 /2 × x = 19 / x × x
x / 2 = 19
Multiply both sides by 2
x / 2 × 2 = 19 × 2
x = 38
_____________________________
Sin( 30 ) = y / x
1 / 2 = y / 38
Multiply both sides by 38
38 × 1 / 2 = 38 × y / 38
38 / 2 = y
19 = y
y = 19
Answer:

Step-by-step explanation:
4 * 45 = 180
265 - 180 = 85
85/5 = 17
They sold 17 rolls of patterned wrapping paper.
Answer:
The minimum sample size required to create the specified confidence interval is 2229.
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.
What is the minimum sample size required to create the specified confidence interval
This is n when 





Rounding up
The minimum sample size required to create the specified confidence interval is 2229.