We have to define an interval about the mean that contains 75% of the values. This means half of the values will lie above the mean and half of the values lie below the mean.
So, 37.5% of the values will lie above the mean and 37.5% of the values lie below the mean.
In a Z-table, mean is located at the center of the data. So the position of the mean is at 50% of the data. So the position of point 37.5% above the mean will be located at 50 + 37.5 = 87.5% of the overall data
Similarly position of the point 37.5% below the mean will be located at
50 - 37.5% = 12.5% of the overall data
From the z table, we can find the z value for both these points. 12.5% converted to z score is -1.15 and 87.5% converted to z score is 1.15.
Using these z scores, we can find the values which contain 75% of the values about the mean.
z score of -1.15 means 1.15 standard deviations below the mean. So this value comes out to be:
150 - 1.15(25) = 121.25
z score of 1.15 means 1.15 standard deviations above the mean. So this value comes out to be:
150 + 1.15(25) = 178.75
So, the interval from 121.25 to 178.75 contains the 75% of the data values.
<span><span>The answer to the question is:</span></span>
<span><span /></span><span><span>−<span>12</span><span>(x−12)</span></span>
</span>
Answer:
That is what the expression would be
Answer:
The equation is 
at a rate of -23%.
Step-by-step explanation:
Decay can be represented by the equation 
. We can find the rate at which it decays by using t=3 hours and A=3000. This means 
in this context.
After substituting, we divided by 6000 to each side to get 0.5 on the left. Now to solve for r, we will take the natural log of both sides and use log rules to isolate r.
We know 
so we were able to cancel it out and divide both sides by 3.
We solve with a calculator 
We change -0.23 into a percent by multiplying by 100 to get -23% as the rate.
The equation is
