You calculated the standard deviation of the sample mean differences to be 0.69. You also calculated the sample mean difference to be 1.74. Now you’ll determine whether the difference is significant. For the purpose of constructing the confidence interval, assume that there’s no difference between the population means.

I think its the 3rd one

Step-by-step explanation:

blue marble is 15 times out of 50 = 15/50 reduces to 3/10

landing on tails is 24 out of 50 = 24/50 reduces to 12/25

to find the probability of both multiply together:

3/10 x 12/25 = 3 x 12 / 10 x 25 = 36/250

if you multiplied the numerator and denominator by 10 you get 360/2500.

the answer is 360/2500

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