If you know what grade you got on each assignment, how do you calculate your overall grade? Find the score that you got most often.

Line up all the scores in order and cross out numbers until you get to the middle number.

Add up all the scores and divide by the number of assignments.

Add up all the scores and divide by 100.

Is there supposed to be a question?

Add up all the scores and divide by the number of assignments.

Step-by-step explanation:

That would be the "Mean" or the average score

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.