Total jellybeans: 7 + 5 + 12 + 4 = 28
Total blue = 7
Probability of picking blue = blue/ total = 7/28 = 1/4
The blue one is returned and then another jellybean is picked.
Total red = 12
Probability of picking red = red/ total = 12/28 = 3/7
Probability of picking a blue and then picking a red one = blue x red
1/4 x 3/7 = 3/28
Answer: 3/28
