First we have to divede the tota of students into the sice of each grop so:

So we can aproximate this to a whole number so:
Answer:
The 13th number in the Fibonacci sequence is 144.
Step-by-step explanation:
The sequence from the first to the 13th number is: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144.
1,2,3,4,6 are factors of 12
5/6 is the probability of getting a factor of 12
1/2 is the probability of getting a tail
5/6*1/2 = 5 /12
Answer: 5/12
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