Suppose Y is a continuous variable whose density gives the following probabilities:

Question

Pr{ Y < -3 } = 0.05
Pr{ -3 < Y < -1 } = 0.15
Pr{ -1 < Y < 0 } = 0.3
Pr{ 0 < Y < 1 } = 0.3
Pr{ 1 < Y < 3 } = 0.15
Pr{ Y > 3 } = 0.05

Compute Pr{ Y > 0 } = ????

Thank you!

Answer 1

Clearly that would be 0.3 + 0.15 + 0.05 = 0.5

Makes sense, since both the intervals and the probabilities are symmetric.

Extra credit: what is the probability that Y=0?

Answer 2

That's equal to zero :) :) :)

For this question I got .45 and it was automatically marked as wrong so I was frustrated!

Thank you!