gjhfdfg
Evaluating expressions,
Delete
Share
This Question is Closed
gjhfdfg
Best Response
You've already chosen the best response.
0
Easiest problem ever, but I forgot how to do them,
|dw:1361117139126:dw|
Can someone show me step by step how to solve this or create a problem giving me an example? Thanks.!
muhammad9t5
Best Response
You've already chosen the best response.
0
\[1-\frac{ 694 }{ 896 }\] do you mean?
gjhfdfg
Best Response
You've already chosen the best response.
0
No, its P
muhammad9t5
Best Response
You've already chosen the best response.
0
then p4 do you mean its power or 4 is multiplied?
muhammad9t5
Best Response
You've already chosen the best response.
0
like p4 or \[p^4\]
gjhfdfg
Best Response
You've already chosen the best response.
0
I have no idea... It just says 6P4,
gjhfdfg
Best Response
You've already chosen the best response.
0
Noo, its not that, I'll take a screenshot
muhammad9t5
Best Response
You've already chosen the best response.
0
ok... i am waiting for screenshot.
gjhfdfg
Best Response
You've already chosen the best response.
0
This is the problem,
muhammad9t5
Best Response
You've already chosen the best response.
0
this is Permutation.
hartnn
Best Response
You've already chosen the best response.
1
ohh..its permutation!
gjhfdfg
Best Response
You've already chosen the best response.
0
I also have this problem that includes a exclamation mark, |dw:1361117585779:dw|
Do you know what its for?
gjhfdfg
Best Response
You've already chosen the best response.
0
& whats permutation? O_O
I have never ever heard of that
hartnn
Best Response
You've already chosen the best response.
1
\(!\)
means a factorial.
hartnn
Best Response
You've already chosen the best response.
1
\(n!= n(n-1)(n-2).......3.2.1\)
when n is a whole number.
like for example
5! = 5*4*3*2*1 = 120
muhammad9t5
Best Response
You've already chosen the best response.
0
answer is 1 it means that you need to expand 6 as 4 times and 8 as 6 times.
muhammad9t5
Best Response
You've already chosen the best response.
0
1/56
hartnn
Best Response
You've already chosen the best response.
1
before getting to permutation, you should know what a factorial ! is .
gjhfdfg
Best Response
You've already chosen the best response.
0
OH.! so I had something like 10! I would have to do 10*9*8*7*6*5*4*3*2*1= etc..?
hartnn
Best Response
You've already chosen the best response.
1
yes, thats correct.
muhammad9t5
Best Response
You've already chosen the best response.
0
6P4= 6*5*4*3
and
8P6= 8*7*6*5*4*3
muhammad9t5
Best Response
You've already chosen the best response.
0
yes you are correct.
hartnn
Best Response
You've already chosen the best response.
1
do you want to know how to get that^ ?
gjhfdfg
Best Response
You've already chosen the best response.
0
I feel like I've done this stuff in 8th grade but had forgotten how to do some of this.
These questions are for my pre-cal class & I found it odd that I had a probability question in there
muhammad9t5
Best Response
You've already chosen the best response.
0
yes.
hartnn
Best Response
You've already chosen the best response.
1
\(\huge ^nP_r = \dfrac{n!}{(n-r)!}\)
gjhfdfg
Best Response
You've already chosen the best response.
0
So basically I had to do the factorial (!) to the 6P & 8P?
muhammad9t5
Best Response
You've already chosen the best response.
0
yes.
hartnn
Best Response
You've already chosen the best response.
1
\(\huge ^nP_r = \dfrac{n!}{(n-r)!} \\\huge ^6P_4 = \dfrac{6!}{(2)!} \\ \huge 8P_6 = \dfrac{8!}{(2)!}\)
gjhfdfg
Best Response
You've already chosen the best response.
0
Everything on the left side of the = is confusing to me
hartnn
Best Response
You've already chosen the best response.
1
in the formula of nPr ?
its just a formula, so for 6P4, i plugged in n=6 and r=4 in the standard formula.
gjhfdfg
Best Response
You've already chosen the best response.
0
How would you know which ones to plug in?
Because in one you have 6P4 & in the next 8P6, I don't get how you go to that?
hartnn
Best Response
You've already chosen the best response.
1
n is before P , r is after P .
in 6P4 , 6 is before P (so, n=6) and 4 is after P (so r=4)
does this makes sense ?
gjhfdfg
Best Response
You've already chosen the best response.
0
Ah, it does now.! :-)
Thanks you guys both for explaining this to me.!
hartnn
Best Response
You've already chosen the best response.
1
Thank me when you get to correct answer.
gjhfdfg
Best Response
You've already chosen the best response.
0
What do you mean?
hartnn
Best Response
You've already chosen the best response.
1
i meant to ask you, whether you could now figure out the answer of that question...
gjhfdfg
Best Response
You've already chosen the best response.
0
I do the factorial, 8*7*6*5*4*3*2*1, I thought?
gjhfdfg
Best Response
You've already chosen the best response.
0
& then divide my answer by 2?
hartnn
Best Response
You've already chosen the best response.
1
thats for 8P2
gjhfdfg
Best Response
You've already chosen the best response.
0
Then I'm lost again,
hartnn
Best Response
You've already chosen the best response.
1
i never said you are wrong. its just not the final answer.
gjhfdfg
Best Response
You've already chosen the best response.
0
Then I do the same with the 6
hartnn
Best Response
You've already chosen the best response.
1
6P4 = 6*5*4*3
8P2= 8*7*6*5*4*3
Question asks, 1- 6P4/8P2 = 1- 6*5 / 8*7*6*5 = 1- 1/(8*7)
ok ?
gjhfdfg
Best Response
You've already chosen the best response.
0
Ah, I wasnt paying attention to the 1,
gjhfdfg
Best Response
You've already chosen the best response.
0
Would I have to subtract the 1 from the 6 & start factoring 5?
hartnn
Best Response
You've already chosen the best response.
1
no...
first division operation is performed, so 6*5*4*3 will get cancelled from numerator and denominator, and what remains is just 1- 1/(8*7)
which i've already shown.
gjhfdfg
Best Response
You've already chosen the best response.
0
Thats confusing
hartnn
Best Response
You've already chosen the best response.
1
ok, clear till this :
6P4 = 6*5*4*3
8P2= 8*7*6*5*4*3
gjhfdfg
Best Response
You've already chosen the best response.
0
Got that...
hartnn
Best Response
You've already chosen the best response.
1
now divide them
6P4/8P2 =.... ?
gjhfdfg
Best Response
You've already chosen the best response.
0
I got 0.0178 etc...
Thats not right..
hartnn
Best Response
You've already chosen the best response.
1
keep it in fractions..
gjhfdfg
Best Response
You've already chosen the best response.
0
I got 360 from 6*5*4*3 & 20160 from the factorial of 8.
gjhfdfg
Best Response
You've already chosen the best response.
0
How would I keep it in fractions?
hartnn
Best Response
You've already chosen the best response.
1
you can also cancel out like this :
|dw:1361120576575:dw|
got that ?
gjhfdfg
Best Response
You've already chosen the best response.
0
Ah, got it.! I wasnt thinking about canceling out
hartnn
Best Response
You've already chosen the best response.
1
ask if any more doubts.
gjhfdfg
Best Response
You've already chosen the best response.
0
What happened to the 4 & 2?
hartnn
Best Response
You've already chosen the best response.
1
i just realized i mistyped 8P6 (and have written 8P2 instead)
4 and 2 where ?
gjhfdfg
Best Response
You've already chosen the best response.
0
The 4 after the P and the 2 after the other P
hartnn
Best Response
You've already chosen the best response.
1
oh, we used the formula, right ?
6-4 = 2, so 2! in the denominator
8-6= 2, so 2! in the denominator
gjhfdfg
Best Response
You've already chosen the best response.
0
OH.! Ok I get it.!
gjhfdfg
Best Response
You've already chosen the best response.
0
1/56 wasnt correct, could it be 55/56 by any chance?
hartnn
Best Response
You've already chosen the best response.
1
?? you forgot '1-...' again ?
1- 1/(7*8)= 1-1/56=(56-1)/56 = 55/56
gjhfdfg
Best Response
You've already chosen the best response.
0
*face palm*
Thank you.
hartnn
Best Response
You've already chosen the best response.
1
welcome ^_^