Abag contains 12 red marbles, 5 yellow marbles, and 15 green marbles. how many additional red marbles must be added to the 32 marbles already in the bag so that the probability of randomly drawing a red marble is ? select your answer. 13 18 28 32 40

= 18 red marbles

Step-by-step explanation:

Let x be the number of red marbles that must be added

Therefore;

New number or red marbles = x+12

Total marbles will be x+32

Thus;

The probability of selecting a red marble = (x+12)/(x+32)

Therefore;

(x+12)/(x+32)=3/5

5(x+12)=3(x+32)

5x+60+3x+96

2x=36

x=18

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.

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