EXPLANATION
We have that the area under the probability density curve is equal to 1.
As the width of the rectangle is 2, the height must be 1/2.
Then, the probability that X is between 0.2 and 1.54 is as follows:
P = 1/2 ( 1.54 - 0.2 )
= 0.67
Hence, the probability is 0.67
