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Freya counted then number of cars that came to a complete stop at stop sign. of the 25 cars, 13 cars came to a complete stop. if Freya observes the next 75 cars that reach the stop sign, how many cars can she expect to come to a complete stop?

User Irena
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1 Answer

3 votes

The expected value can be calculated with the formula


E(x)=x\cdot p(x)

Where p represents the probability, and x represents the new event.

Basically, we just have to find the probability of the 13 cars


p(x)=(13)/(25)=0.52

Then, we multiply by the numbers of cars x = 75.


E(75)=75\cdot0.52=39

Hence, the right answer is 39. The expected value is 39.

User Amit Sharad
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