You can use normal distribution try and know something.This amethod using finite for 00.x^2*e^(-x^2) almost is 0.Chinese, Jewes and Russian are best in Math.This Russian ,I guess, want to check people how to avoid life experience. Please note,You should get it with P(E)=1.If the gold is put very far....If the question changed to P(E)>0.9. You are right.