# It's the least I could do ....

Suppose $$w,x,y$$ and $$z$$ are random real numbers chosen independently and uniformly from the interval $$[0,1].$$

If the expected value of the smallest of $$w,x,y,z$$ is $$\dfrac{a}{b}$$, where $$a$$ and $$b$$ are positive coprime integers, then find $$a + b.$$

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