Let X1X_1X1 and X2X_2X2 be IID random variables with uniform distribution on [0,1][0, 1][0,1]. Define:
What is P(Y≥y∣Z≤z)P(Y \geq y \mid Z \leq z)P(Y≥y∣Z≤z) for any y,z∈[0,1]y, z \in [0, 1]y,z∈[0,1] with y≤zy \leq z?