I need help with #1 and #2 how do I do this?

The answer to your question is below

Step-by-step explanation:

Data

1) AB = 6   BC = 4   AE = 9  ED = ?

Use proportions to solve this problem

              AB / AE = 6/9    (AB + BC) / (AE + ED) = (6 + 4) / (9 + ED)

-Equal both proportions

                              6/9 = 10 / (9 + ED)

-Solve for ED

                             9 + ED = 10(9)/ 6

-Simplification

                             9 + ED = 90/6

                             9 + ED = 15

                                   ED = 15 - 9

-Result

                                   ED = 6

2.-   AB = 12   AC = 16  ED = 5  AE = ?

Use proportions to solve this problem

             AE / AB = AE / 12          AD/AC = (AE + 5) / 16

-Equal both proportions

                          AE/12 = (AE + 5 ) / 16

-Solve for AE

                         16AE = 12(AE + 5)

                         16AE = 12AE + 60

                         16AE -12AE = 60

                                     4AE = 60

                                       AE = 60/4

-Result

                                      AE = 15                          

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.