Probability help (1 Viewer)

[Timothy.Siu]

All the letters of the word ENCUMBRANCE are arranged in a line. Find the total number of arrangements, which contain all the vowels in alphabetical order but separated by at least one consonant.

from JRAHS 03 trial,

 

[Timothy.Siu]

when u subtract the double counts, it could be subtracting AEEUXXXXXXX

so that means u just have to add 8!x4!/(2!x2!x2!) [4 at a time] to that and divide by 12?
or is there sometihng else too

it seems right...but i'm not sure like you aren't

 

[Trebla]

when u subtract the double counts, it could be subtracting AEEUXXXXXXX

Yeah, you're subtracting it ONCE from the total though because it exists twice within the total. So when you subtract, it is therefore included once instead of twice.

 

[Timothy.Siu]

Yeah, you're subtracting it ONCE from the total though because it exists twice within the total. So when you subtract, it is therefore included once instead of twice.

oh i see,
i get it, it seems pretty small though

 

[Trebla]

You should expect it to be reasonably small. The fact that the vowels have to be in alphabetical order reduces the unrestricted case by 1/12 th to 415 800. Then you have to account for the other restriction which reduces this number even further...so the number must be smaller than 415 800 to say the least.

 

[Trebla]

A X E X E X U XXXX
there would be 1260 arrangements already and if u just move the U across one space each time, that'll be 6300 arrangments

i'm pretty sure its above 80k.

In that case, just ignore the working or find a flaw in it

 

[Timothy.Siu]

In that case, just ignore the working or find a flaw in it

lol i already tried and failed but i'll see

 

[Timothy.Siu]

hmm i'm sure someone else can find an error...because there has to be,

this question has been haunting me for like 2 days now...i did try to manual count them and i got 88200. but i'm definitely not sure

 

[clintmyster]

hmm i'm sure someone else can find an error...because there has to be,

this question has been haunting me for like 2 days now...i did try to manual count them and i got 88200. but i'm definitely not sure

whoa manual count

and your actually right!! I looked through my comp and seems i had the paper and solutions!!

 

[Timothy.Siu]

thanks heaps