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Hi
I purchased an HP30b financial calculator and am very satisfied. I used an HP12c for five months, but I didn't get used to the layout of the keys (very polluted look!). I found the HP30b more complete !. I know that the HP30b does the binomial calculation (Math> Probability> Binomial), but I don't know how to enter the data. I made a program for this, but I know that the calculator does it automatically. How do I enter the data for the binomial calculation?

for example: n = 10 k = 1 p = 0.1 I know the answer is 0.3874 (38,74%)

How do I calculate directly with the HP30b?

Thanks!
I don't have the HP30b but I did post on about calculate the Binomial for
the HP-12C since you also got the 12C so you might try this out first and see
if it is harder or easier to do between 30b and 12c

https://www.hpmuseum.org/forum/archive/i...11264.html

for example: n = 10 k = 1 p = 0.1 I know the answer is 0.3874 (38,74%)

Once enter this program to run.

[f] 4 for Fix 4

10 [ENTER] 1 [ENTER] .1 [R/S] display 0.3874

Gamo
(12-30-2020 08:07 PM)FabioBrasil Wrote: [ -> ]Hi
I purchased an HP30b financial calculator and am very satisfied. I used an HP12c for five months, but I didn't get used to the layout of the keys (very polluted look!). I found the HP30b more complete !. I know that the HP30b does the binomial calculation (Math> Probability> Binomial), but I don't know how to enter the data. I made a program for this, but I know that the calculator does it automatically. How do I enter the data for the binomial calculation?

for example: n = 10 k = 1 p = 0.1 I know the answer is 0.3874 (38,74%)

How do I calculate directly with the HP30b?

Thanks!

From the 30b user guide page 23: HP30b userguide

Binomial Functions
The binomial function calculates the probability of having up to k successes out of n throws,
when the probability of success is p.
Enter n and p each followed by = and type k and
navigate to the binomial function in the math menu.

HP-30b learning modules
(12-30-2020 08:07 PM)FabioBrasil Wrote: [ -> ]Hi
I purchased an HP30b financial calculator and am very satisfied. I used an HP12c for five months, but I didn't get used to the layout of the keys (very polluted look!). I found the HP30b more complete !. I know that the HP30b does the binomial calculation (Math> Probability> Binomial), but I don't know how to enter the data. I made a program for this, but I know that the calculator does it automatically. How do I enter the data for the binomial calculation?

for example: n = 10 k = 1 p = 0.1 I know the answer is 0.3874 (38,74%)

How do I calculate directly with the HP30b?

Thanks!

The answer 0.3874 is the probability mass function (PMF) value, which is the probabilty of exactly k successes. The HP-30b doesn't have a built-in function for that. It has a built-in function for the cumulative distribution function (CDF) value, which is the probability of k or fewer successes. The answer for that is 0.7361 (73.61%).

Well, you could use the built-in binomial CDF to calculate for n=10, p=0.1, k=0, store that in a memory, calculate for n=10, p=0.1, k=1, and subtract the previously stored value, but that is cumbersome and error prone. It would be easier to use the PMF formula you already know.
I thank everyone! I was able to get the answer with the Learning Module suggested by the moderator Genes. Through this material, I saw that the binomial in the HP30b is an embedded function calculated for the value of the cumulative distribution function (CDF). Unlike HP Prime that does it directly! I did what Ijabbott suggested and everything went well. Every day I like this calculator more. Thank you and have a great new year!
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