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Please help?!

Erik is performing a marble experiment in math class. His teacher places an equal number of black, red, and white marbles in a bag. Then, Erik randomly takes out a marble, records the result, and puts the marble back in the bag. Each of the first four times Erik takes out a marble, he gets a black marble.

A. What is the theoretical probability of Erik picking a black marble next time? Based on Erik's results, what is the experimental probability of Erik picking a black marble next time?
B. Explain the difference between the two probabilities you found in part A.
C. What is the theoretical probability and likelihood of getting four black marbles in a row?

User Jin Liu
by
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2 Answers

6 votes

Answer: A.theoretical is not counting the results of the experimentssince there are an equal number of red and black and red, the probblity (theoretical) of picking a black one is 1/3

experimental = number of outcomes happened/total number of tests 4 times black, 4 tests, so 4/4 or 100%=experimental proablity

B. experimental considered previous trials and theoretical did not

C. theoretical=(1/4) the trials don't influence each other so1/(4*4)=1/16

⭐︎⭐︎HOPE THIS HELPS YOU!!⭐︎⭐︎

User Torsten Marek
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6.4k points
3 votes
theoretical: desired outcomes/total possible outcomes

the same as it was his first time picking before since the prevous results have no bearing on what this trial will yeild
if he didn't replace the marbles then it would be differnt



experimintal=number of event occurnces/total number of trials
so 4/4 or 100% is experimental
so

equal number of red and black and white
1/3 of the bag is black
therefor the probablity of picking a black marble is 1/3
A. 1/3 is theoretical, 4/4=experimental

B. differnce? dunno sorry

C. 4 in a row
1/3*1/3*1/3*1/3=1/81
User Kosmotaur
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6.2k points