Find the percent of the area under the density curve where x is more than 3.
By definition, the area under a complete density curve is equal to 1. So, the percent of the total area under a portion of the curve is equal to the area under that part of the curve.
We are looking for the area under the density curve when x > 3.
The area of a rectangle is length x breadth
So area = (3) \cdot (0.2) = 0.6
So the percent of the area under the density curve where x is more than 3 is 60%.
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Density Curves (video) | Khan Academy
An introduction to density curves for visualizing distributions. ... Imagine that you have a continuous data set (like the quantity of water that people ... I understand that the area under the curve is the probability of getting an X in that interval. ... get a curve and this type of curve is something that we actually use in statistics and ...
For more information, see Density Curves (video) | Khan Academy