easy   Probability

Beta Difference

A release-checked easy problem for training Continuous Random Variables, Limit Theorems.

Question

Let $X_1,\dots,X_{324},Y_1,\dots,Y_{324} \sim \text{Beta}(1,2)$ IID. Define $S_{324} = X_1 + \dots + X_{324}$ and $T_{324} = Y_1 + \dots + Y_{324}$. Approximate $\mathbb{P}[S_{324} - T_{324} > 10]$. Your answer should be in the form $\Phi(a)$, where $\Phi$ is the standard normal CDF. Find $a$.

Practice focus

This Probability problem is tagged Continuous Random Variables, Limit Theorems. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.

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