Answer:
-6 33/40
Step-by-step explanation:
2 5/8 * -2 3/5
Change each to an improper fraction
2 5/8 = (8*2+5)/8 = 21/8
2 3/5 = (5*2+3)/5 = 13/5
21/8 * -13/5
-273/40
Change to mixed number
40 goes into 273 6 times
6*40 = 240 273-240 =33
-6 33/40
Diego is building a kitchen table and a coffee table. The legs of a kitchen table must be twice the height of a coffee table and there are 4 legs on each table. He writes the expression 4(2x) + 4(x) to model his building plans. What does 2x represent?
2x represents the height of one kitchen table leg. 2x represents the total height of all four kitchen table legs. 2x represents the height of one coffee table leg.<span> 2x represents the total height of all four coffee table legs.</span>
Answer:
A sample of 18 is required.
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 Z-table as such z has a p-value of
.
That is z with a pvalue of
, so Z = 1.88.
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 indicated that the standard deviation was 2.2 days.
This means that 
How large a sample must be selected if the company wants to be 92% confident that the true mean differs from the sample mean by no more than 1 day?
This is n for which M = 1. So



Rounding up:
A sample of 18 is required.
A graph with a dotted line running through the points (-4, 0) and (0, 6) shaded above the origin.