An odd number where the tens digit is double the units digit (between 40 and 70)​

63

Step-by-step explanation:

solution number = xy

x = 2y

40 < xy <70         40 < (2y*10) + y < 70

40<21y<70

40/21 < y < 70/21

1.9 < y < 3.8  

y can be 2 or 3  ... y is odd

y = 3

x = 6

Odd number: 63

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.

step-by-step explanation: