Find the total number of elements that satisfy this condition: (n/3)=20

Status
Not open for further replies.
I never said you should multiply 3! by 6.

You said you doubt how to multiply 3! by 6.

I said I don't understand why you want to do that multiplication (but it is 36).
 
Okay, I misunderstood you then. back to
1627695386541.png

now, what should i do, any hints?
 
[math]\frac{\cancel{6}^1}{1} \cdot \frac{n!}{(n-3)! \cdot \cancel{6}_1} = (6)(20)[/math]
That's how the sixes cancel.

[imath]\;[/imath]
 
Same thing i did except i did not do the fraction cos the 1 is implied there. now, Any hints?, and thanks, Otis for sticking with me.
1627695603556.png
 
So why did you multiply the sixes, instead of cancelling them?

?
 
So why were you trying to multiply the sixes, instead of cancelling them?

?
Cos i misunderstood what you said ,i thought you were telling me it was alright to go ahead and multiply 6 *3! and that was 36. i got you wrong.
if you take a peek at post# 31 i had it right. i got confused by your statement,. just that.
 
Next, do you understand how to simplify 10!/7!

How about 8!/5!

[imath]\;[/imath]
10!=10*9*8*7*6*5*4*3*2
7!=7* 6*5*4*3*2
I cancel out repeated numbers in each
8!=8* 7*6*5*4*3*2
5!=5*4*3*2
cancel out repeated numbers,
or common factors like you call them.
 
Those are incorrect.

Students need to learn the definition of factorial before trying factorial exercises.

Your learning approach seems backwards.

[imath]\;[/imath]
I rectified that above. At #48.
I know how to develop a factorial expressions.
You are not reading my answers otis.
Please, refer to my post at 48 and tell me if that is wrong. It is not.
I omitted the *1 cos it makes no difference at all.
 
Last edited:
refer to my post at 48 and tell me if that is wrong. It is not.

After your mistake was pointed out, the forum software shows that you went back and altered your post.

Then you immediately claimed that your post was not read correctly.

That is dishonest.

?
 
10!=10*9*8*7*6*5*4*3*2
7!=7* 6*5*4*3*2
I cancel out repeated numbers in each
8!=8* 7*6*5*4*3*2
5!=5*4*3*2
cancel out repeated numbers,
or common factors like you call them.
If 10!=10*9*8*7*6*5*4*3*2 and 7!=7* 6*5*4*3*2, what is 10!/7!?
 
After your mistake was pointed out, the forum software shows that you went back and altered your post.

Then you immediately claimed that your post was not read correctly.

That is dishonest.

?
Good bye to the forum. Good luck. I wish you all the best. Thanks for everything and all the help you offered.
 
Status
Not open for further replies.
Top