Iknow twice as many jokes as my friend does. together we know 60 different jokes. my friend and i both know the same three jokes. how many jokes do i know? how many jokes does my friend know?

9514 1404 393

Step-by-step explanation:

The total of the numbers we know individually is more than the total of different jokes we know by the number we both know. That is, adding the number I know and the number my friend knows, I get 60 +3 = 63.

Since I know twice as many as my friend, I know 2/3 of that total, or 42 jokes. My friend knows 1/3 of the total, half the number I know, or 21 jokes.

Then I know 42 -3 = 39 different jokes from my friend. My friend knows 21 -3 = 18 different jokes from me. We know 3 jokes in common, so the total number of jokes we know is 39 +18 +3 = 60 jokes.

I know 42 jokes; my friend knows 21.

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.

17

step-by-step explanation: