Answer:

And we can find this probability using the normal standard table or excel and we got:

The figure shows the calculation for this case.
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the hardness of a population, and for this case we know the distribution for X is given by:
Where
and 
We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:

And we can find this probability using the normal standard table or excel and we got:

The figure shows the calculation for this case.
9514 1404 393
Answer:
- 4% fund: $39,000
- 52% fund: $1000
Step-by-step explanation:
Let x represent the amount invested at 52%. Then (40000-x) is the amount invested at 4%. The total annual interest is ...
0.52x +0.04(40000-x) = 2080
0.48x = 480 . . . . . . . . . subtract 1600, simplify
x = 1000 . . . . . . . . . divide by 0.48
Then the amounts invested in each fund are ...
4% fund: $39,000
52% fund: $1000
Answer:
The shadow is 11 Ft. away from the pole base.
Step-by-step explanation:
I just usually do this trick in situations like these where if <em>x</em> equals 1, and <em>y</em> equals 2, then <em>z </em>is gonna be 3. 2 goes after 1, and 3 goes after 2. This trick can work in other counting-up situations like this, as long as the number go up, and are right next to each other.
Answer:
y = x + 6
Step-by-step explanation:
The y-intercept is (0, 6). This is where the line crosses the y-axis.
The slope is 4/4, or 1: m = 1
The equation of the line is therefore y = x + 6
From the choices above, <span>the formula that could be used in cell is B2.</span>B. 3 * E2 - (C2 + D2).