What is a ! Factorial ! ?

The basics 18 Comments

Factorials are a concept introduced in elementary algebra. They are also used in statistics classes, especially in combination and permutation calculations. Factorials are products of every whole number from 1 to n. For example, 3! is 3 x 2 x 1 = 6.  Most calculators have a factorial (!) button, but Google can also do the work for you!

  • Go to the search bar at Google.com
  • Type in a factorial, such as 36!
  • Press enter
  • 12 ! = 479 001 600

Google can also figure out more complicated factorials for you, such as 36! / (12-10)!6!. However, make sure you put in parentheses and a multiplication sign (just as you would on any basic calculator):

36! / ((12-10)! * 6!) = 2.58328699 × 1038 (☨)

☨ Google Calculator Tip: To multiply using google, use an asterisk (*) rather than a “×” symbol.

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18 Responses to “What is a ! Factorial ! ?”

  1. Evelyn Snyder said:

    Sep 14, 09 at 3:23 pm

    My biggest challenge with chapter 2 was the factorials. The sixth-edition Elementary Statistics by Allan G. Bluman is well worth the $166.00 +. Factorials is defined and explained in chapter 4, section 5, pages 218 and 219. I have had to read and read this section several times and now I feel more comfortable with factorials. One of the ways to identify a factorial problem is with the factorial notation of the usage of the explanation point (s). A factorial is a series of positive integers that are used to calculate the outcome of how to measure an outcome, a good example is in the textbook, page 219: the number to the left of C and the number to the right of C determine how many factorials are needed to solve this equation and sometimes more than one equation is needed to solve a word problem. We use factorials without realizing it when we have an x amount of women and an x amount of men to be chosen to serve our country; and as to how many automobiles does car maker A, B or C market in a particular make, model and color. This is difficult to learn, but well worth the effort, sweat and tears!

  2. Angie Widdows said:

    Sep 17, 09 at 6:32 pm

    The explanation provided helps but my biggest problem with factorials is figuring out my calculator. Possibly a calculator walkthru on how to run factorials would be helpful. Maybe something like, if you have this type of calculator, this is what you need to push in order to find the factorial key

  3. Stephanie said:

    Sep 18, 09 at 4:09 am

    Angie,

    Good point. I’m planning to put together something for the different calculators at a later date.

    Have you tried the permutations and combinations calculator?

    Stephanie

  4. Donna Allen said:

    Sep 19, 09 at 9:37 am

    I also could definitely use some help in figuring out the calculator. There are functions on there that I have never had to use before and am very unfamiliar. I think factorials were better explained here in the blog than in the book we were required to buy-it unfortunately was of little help.

  5. Jennifer Foster said:

    Sep 20, 09 at 8:06 am

    I too am having a lot of problems with factorials. In this section is suggest that we use Google and it will be able to help find the answer, but I am still lost. For example, I entered 22! / (22-4)!4! into google and got a bunch of sites with pharmacy codes and nothing pertaining to help on this question. Do I need to get a scientific calculator?

  6. Stephanie said:

    Sep 20, 09 at 10:55 am

    I think you may be entering the formula into Google incorrectly. Check out the formula in the article–it’s different from the 22! / (22-4)!4! you entered into Google. With any calculator (including scientific ones), you would need to use parentheses: 22! / ((22-4)! * 4!). Also note that I added a multiplication sign * because Google doesn’t understand that 4!4! means 4! * 4!.

    Hope that helps! You are certainly welcome to buy a calculator if you feel that it will help you, but you don’t have to have one for this course.

  7. Jennifer Thomas said:

    Sep 20, 09 at 12:02 pm

    On a T-84 calculator you input the number and then press the math button, tab over to PRB and enter 4. I know how to input this on the caclulator but I don’t know how to calculate on my own. I didn’t find the book to be very helpful.

  8. Kalynn Grabau said:

    Sep 21, 09 at 8:46 am

    I also had issues trying to figure this stuff out on my calculator. I think I sat there for hours trying to figure out how to convert by decimal answers into fractions HAHA But I figured it out!

  9. Stacey Bell said:

    Sep 21, 09 at 8:56 am

    I just used google using your steps and it worked GREAT!!! I now have a better understanding of what I am doing for this problem. Thank you!

  10. Stephanie said:

    Sep 21, 09 at 9:59 am

    Awesome…glad it helped!

    Stephanie

  11. Stephanie said:

    Sep 21, 09 at 10:00 am

    Great. I am glad the site is helping a little. Stats can be a difficult subject to tackle!

    Stephanie

  12. Karin Martindale said:

    Sep 21, 09 at 11:53 am

    I was manually entering the counting problems into my calculator one at a time (22x21x20 etc.) which worked but it took forever! I wish I would have read this post before Chapter was over. Google is a great tool. I am going to write down the calculations in my notes for 1!-30! just for an easy reference. Thanks everyone!

  13. Mary Johnson said:

    Sep 23, 09 at 2:30 pm

    I wish I would have seen this earlier. I had to google what the ! meant. Then I didn’t realize until today my calculator had this feature. Maybe it will get easier now.

  14. Stephanie said:

    Sep 24, 09 at 6:19 am

    Glad it helped :)

  15. Sarah Joyner said:

    Sep 27, 09 at 7:45 am

    I just used Google to do this and it worked and I liked how it showed to input it in the calculator because I will not always have access to a computer when doing these sorts of problems. One suggestion for your explanation up top would be to explain the steps to put it in the calculator. For someone like me, who is statistics illiterate, I need every single tiny step laid out for me or I will not understand it. Thank you for directing me to this section to help me with the factorial problems.

  16. Vanessa DuBarry said:

    Dec 14, 09 at 10:23 pm

    google really did help with this! it made it much easier.

  17. crystal lydick said:

    Feb 08, 10 at 6:26 pm

    Wish I would have read this a couple of weeks ago, maybe this will help me now, I will work on this tomorrow. This class is pretty difficult so far. Thanks goodness I am only taking 2 classes, because I could have never handled any more than that.

  18. Statistics How To» Blog Archive » How to Calculate TI 83 Permutations and TI 83 Combinations said:

    Mar 16, 10 at 11:00 am

    [...] 3 people for a work party). While doing this by hand is cumbersome (the equation you use involves factorials like n! and r!), the calculator can figure it out at the press of a [...]

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