If you do it 144 times that is (3+9)*12
This means that 12 times 3 red and 9 blue counters will be chosen that means that 9 blue counters will be chosen 12 times. 9*12 is 108.
This means blue counters will be chosen 108 times.
This can be checked as 108/3 would give you the number of red counters which is 36 and 108+36 is 144
The answer is 94 2/5. All you have to do is multiply 1/5 by 472. Then, you'll have your answer.
Hope this helps! :D
X1+X2 Y1+Y2
--------- , ---------
2 2
Thats the equation. You write that (the equation above) in parentheses.
Part A
Use the binomial probability distribution formula.
p = 0.54 = probability of getting a purple marble
n = 5 = sample size
x = 2 = number of purple we want to get

The
portion is from the nCr combination formula. The exclamation marks indicate a factorial.
Alternatively, you could use Pascal's Triangle for that portion.
<h3>Answer: 0.283831776</h3>
This decimal value is exact. Round it however you need to.
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Part B
To find the expected value, aka the mean, we multiply the sample size and probability of getting a purple marble on any single selection.
n*p = 5*0.54 = 2.7
<h3>Answer: 2.7</h3>