Respuesta :
Answer:
You would have to add 4 blue marbles
Step-by-step explanation:
there are a total of 12 marbles, 4 of them being blue.
If you add 4 blue ones, there would be a total of 16 marbles and 8 of them would be blue.
8/16 = 1/2
Therefore, 4 blue marbles need to be added for the chance to draw one to be 1/2 or 50%
Answer:
Step-by-step explanation:
Since there is 1 green, 2 yellow, 4 blue, and 5 red we start with 12 marbles. For the probability of picking a blue to be 1/2 we must satisfy.
(b+x)/(12+x)=1/2. (Where x is the number of blue marbles added)
2(b+x)=12+x
2b+2x=12+x
2b+x=12
x=12-2b, since we started with 4 blue marbles
x=12-2(4)
x=12-8
x=4
So we would need to add 4 blue marbles to make the probability of picking a blue 1/2.