Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
Ishaan94
Group Title
Number of arrangements of the set \(\{a_1,a_2, \ldots, a_{10}\}\), so that \(a_1\) is always ranked above \(a_2\).
 2 years ago
 2 years ago
Ishaan94 Group Title
Number of arrangements of the set \(\{a_1,a_2, \ldots, a_{10}\}\), so that \(a_1\) is always ranked above \(a_2\).
 2 years ago
 2 years ago

This Question is Closed

Ishaan94 Group TitleBest ResponseYou've already chosen the best response.0
@satellite73 @eliassaab
 2 years ago

Ishaan94 Group TitleBest ResponseYou've already chosen the best response.0
@experimentX :D
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
dunno i hate counting but if \(a_1\) is first then there are 9 choices for \(a_2\) if \(a_1\) is second there are 8, if \(a_1\) is third there are 7, so i guess we can use that
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
without thinking too hard i get an answer that could easily be wrong, namely \[9+8+7+6+5+4+3+2\]
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
oops +1 at the end because \(a_1\) could be 9th leaving one possibility for \(a_2\)
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
oh crap that is all wrong
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
but idea is probably right. if \(a_1\) is first there are 9! arrangements
 2 years ago

experimentX Group TitleBest ResponseYou've already chosen the best response.1
I think it could be 1(9+8+7+6+5+4+3+2+1)8!
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
if \(a_1\) is second there are 8 times 8! arrangements
 2 years ago

experimentX Group TitleBest ResponseYou've already chosen the best response.1
dw:1340650357123:dw
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
so yeah, experimentX has it
 2 years ago

Ishaan94 Group TitleBest ResponseYou've already chosen the best response.0
experimentx's makes sense. and so does satellite's idea. Medal each other.
 2 years ago

Ishaan94 Group TitleBest ResponseYou've already chosen the best response.0
experiemntx's answer*
 2 years ago

Ishaan94 Group TitleBest ResponseYou've already chosen the best response.0
thank you. :)
 2 years ago

satellite73 Group TitleBest ResponseYou've already chosen the best response.1
that answer makes sense to me. i was totally wrong the first time, and didn't know that formula but now that i see it it is clear
 2 years ago

experimentX Group TitleBest ResponseYou've already chosen the best response.1
well that solves it ;)
 2 years ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.