An eight-sided die has the numbers 1 through 8 on its eight faces. What is 2 points the expected value when rolling the die? *
O 3.6
04
4.5
06

4.5

Step-by-step explanation:

(1/8)*1 + (1/8)*2 + (1/8)*3 + ... +(1/8)*8

or

(1/8)*(1  2 + 3 + 4 + 5 + 6 + 7 + 8) = (1/8)*36 = 4.5

We can use a shortcut to sum the numbers 1 through 8.  It is given by 8*(8+1)/2.

step-by-step explanation:

the multiplicative inverse of a fraction a/b is b/a. for the multiplicative inverse of a real number, divide 1 by the number. for example, the reciprocal of 5 is one fifth 1/5 or 0.2, and the reciprocal of 0.25 is 1 divided by 0.25, or 4.

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.