Answer:
Explanation:
let's denote the mean of the test by u. We know that a score of 41 falls three standard deviations below the mean, and a score of 73 falls one standard deviation above the mean.
From the first statement, we have:
41 = u-3o
where o is the standard deviation.
From the second statement, we have:
73 = u + o
Now we can use these two equations to solve for u. We can start by solving for o and the first equation:
41 = u -3o
41 - u = -3o
o = (u - 41) /3
We can substitute this expression for o into the second equation:
73 = u + o
73 = u + (u - 41 ) / 3
219 = 3u + u - 41
260 = 4u
u = 65
Therefore, the mean of the test is 65.