How can I calculate it with my HP...?

[PANAMATIK]

(04-16-2015 04:13 PM)Csaba Tizedes Wrote:  Can anybody give me a good advice how can I calculate the following probability example on my HP-20S?

p= Cn,r(5,2) × Cn,r(85,3) ÷ Cn,r(90,5)

The right result is for FIX 4 is 0.0225

Thanks!
Csaba

If you use registers it can easily be done with
5 INPUT 2 Cn,r STO 0
85 INPUT 3 Cn,r STO 1
90 INPUT 5 Cn,r STO 2
RCL 0 x RCL 1 / RCL 2 =

Bernhard