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Short-Term Actuarial Math Old Exam C Forum

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  #1  
Old 01-13-2015, 08:09 PM
PrinceNReserve PrinceNReserve is offline
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Default Evaluating binomial coefficients with fractions

Can someone explain to me why 2.5 choose 2 = 1.875? Thanks!
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Old 01-13-2015, 08:17 PM
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Where did you come across that? In this exam you should only come across integer binomial coefficients, at least in my experience. In any case,

You can use the gamma function or just remember that and .
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Old 01-13-2015, 08:53 PM
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Where did you come across that? In this exam you should only come across integer binomial coefficients, at least in my experience.
Not necessarily. I assume the OP is going off the ASM convention, where . So in this case,
.

I doubt the Gamma function is involved, since the final answer is very "clean."
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Old 01-13-2015, 08:59 PM
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Not necessarily. I assume the OP is going off the ASM convention, where . So in this case,
.

I doubt the Gamma function is involved, since the final answer is very "clean."
The gamma's cancel in the numerator and denominator.
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Old 01-13-2015, 09:12 PM
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The gamma's cancel in the numerator and denominator.
Lemme see.

.

Okay, so it does.

Although, I would not suggest doing it this way on the exam, since the formula can be easily figured out from the C tables.
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Old 01-13-2015, 09:19 PM
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Not necessarily. I assume the OP is going off the ASM convention, where . So in this case,
.

I doubt the Gamma function is involved, since the final answer is very "clean."
Thanks. I did see it from the ASM. Then, would

. ?
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Old 01-13-2015, 09:23 PM
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Thanks. I did see it from the ASM. Then, would

. ?
Yep, you're good there - but I wouldn't bother recognizing that formula. If you need it, 99% chance you would use it for the negative binomial probability function, and it's right in the C tables.
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Old 01-13-2015, 09:29 PM
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Yep, you're good there - but I wouldn't bother recognizing that formula. If you need it, 99% chance you would use it for the negative binomial probability function, and it's right in the C tables.
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