SOLUTION: I am really lost with this concept: Factorial expressions Find the value of the following: {{{(11! 12!)/(8!10!)}}} If your answer is not an integer, write it as an exact

Question 548996: I am really lost with this concept:
Factorial expressions
Find the value of the following:

If your answer is not an integer, write it as an exact fraction.
Found 2 solutions by Alan3354, mathie123:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Factorial expressions
Find the value of the following:
11! 12!
-------
8! 10!
-------------
11!/10! = 11, so cancel those
= 11*12!/8!
-----------
12!/8! = 12*11*10*9
---
= 11*12*11*10*9
= 130680

Answer by mathie123(224) (Show Source): You can put this solution on YOUR website!
We know that n!=n*(n-1)*(n-2)*...*2*1
So we can expand

to get:

Now... looking at the expression above... can anything divide out (i.e. get rid of any number that appears in the numerator and denominator). This leaves:

Now this expression can be calculated as an integer on your calculator... I will leave that for you to do .
Obviously if we had large numbers... it wouldn't be a good idea to write out the whole factorial, but you may be able to see some patterns once you do some examples... (try to find them)
Hopefully this helps a bit... let me know if you are still unsure

RELATED QUESTIONS
Factorial expressions Find the value of the following: 11!11! ------ 13!10! If... (answered by stanbon)
I need help with this factorial expression:find the factorial of: 12!/11! 12!/13! Thanks... (answered by DrBeeee)
Find the value of the following: 7!12! _____ 10!11! If your answer is not an... (answered by solver91311)
Factorials 10!11! ------ 9!14! I understand what a factorial is. I'm just... (answered by JulietG)
I am lost. I have no idea what this question is even supposed to mean. 2.) In the... (answered by greenestamps)
Find the value in the following expression: |-8|-|-12| I am having a hard time... (answered by jsmallt9)
Dear math teacher, I am having difficulties with the following problem: (a)Find n;... (answered by jim_thompson5910)
Hello, I am having a really hard time with this. I have tried to complete several of the... (answered by jim_thompson5910)
Solve the following quadratic equations. 4x^2=13x+12... (answered by HyperBrain,stormy)