Two different buses start their routes at the same corner at 9 A. M. Buses from one route stop at the library every 9 minutes. Buses from the other route stop at the library every 12 minutes. In what number of minutes will both buses end up at the library?

In 36 minutes both buses  will end up at the library.

Step-by-step explanation:

Given: Buses from one route stop at the library every 9 minutes.

Buses from the other route stop at the library every 12 minutes.

The number of minutes in which both buses will end up at the library= LCM(9,12)

Now , 9= 3 x 3

12= 2 x 2 x 3

LCM(9,12) = 2 x 2 x 3 x 3 = 36

In 36 minutes both buses  will end up at the library.

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.

square root of 36/6 = 2.449489743

square root of 16/6 = 1.632993162

square root of 6 = 2.449489743

the answer is square root of 16/6 because the square root of 36/6 is the same answer as square root of 6 = 2.449489743