posted by Sabrina on .
A professor informs her class that a test is very difficult, but the grades will be curved. Scores for the test are normally distributed with a mean of 25 and a standards deviation of 5. If she curves the grades by adding 50 to each grade, What is the new mean? What is the new standard deviation?
The new mean will be 25+ 50 = ?
The standard deviation will remain the same.
The new mean is 75 (25 + 50); however the standard deviation stays at 5 because she adds the same amount of points to all grades, so the curve is just shifting up rather than changing shapes.