1. Convert the mixed numbers into improper numbers (-3 2/5 = -17/5 and 8 1/5 = 41/5). Then add 17/5 to both sides when means b=58/5
2. Multiply both sides by the reciprocal of -7/3 (which is -3/7). So n=18
There really is no single "obvious" choice here...
Possibly the sequence is periodic, with seven copies of -1 followed by six copies of 0, or perhaps seven -1s and seven 0s. Or maybe seven -1s, followed by six 0s, then five 1s, and so on, but after a certain point it would seem we have to have negative copies of a number, which is meaningless.
Or maybe it's not periodic, and every seventh value in the sequence is incremented by 1? Who knows?
I'll go ahead and assume the latter case, that the sequence is not periodic, since that's technically somewhat easier to manage. We can assign the following rule to the

-th term in the sequence:


for

.
So the generating function for this sequence might be

As to what is meant by "closed form", I'm not sure. Would this answer be acceptable? Or do you need to find a possibly more tractable form for the coefficient not in terms of the floor function?
Answer:
D
Step-by-step explanation:
there are no statements to see of they are correct
Red is 20 and you spin it 50 times so 2/5 chance is red so that makes 3/5 chance not red