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There-are-many-ways-to-arrange-3-red-balls-and-9-black-balls-in-a-circle-so-that-there-are-a-minimum-of-2-black-balls-between-2-adjacent-red-balls-a-180-8-b-240-7-c-364-6-d-282-4




Question Number 200051 by cortano12 last updated on 13/Nov/23
  There are many ways to arrange 3 red   balls and 9 black balls in a circle   so that there are a minimum of 2  black balls between 2 adjacent red  balls.  (a) 180×8!    (b) 240×7!    (c) 364×6!   (d) 282×4!    (e) 144×5!
Therearemanywaystoarrange3redballsand9blackballsinacirclesothatthereareaminimumof2blackballsbetween2adjacentredballs.(a)180×8!(b)240×7!(c)364×6!(d)282×4!(e)144×5!
Commented by mr W last updated on 13/Nov/23
different or identical balls?
differentoridenticalballs?
Commented by cortano12 last updated on 13/Nov/23
different balls
differentballs
Answered by mr W last updated on 13/Nov/23
to arrange the red balls: 2!=2  to arrange the black balls:  2+2+5 ⇒((3!)/(2!))×2!×2!×5!=1440  2+3+4 ⇒3!×2!×3!×4!=1728  3+3+3 ⇒3!×3!×3!=216  ⇒2×(1440+1728+216)=6768 ✓  ⇒answer (d)
toarrangetheredballs:2!=2toarrangetheblackballs:2+2+53!2!×2!×2!×5!=14402+3+43!×2!×3!×4!=17283+3+33!×3!×3!=2162×(1440+1728+216)=6768answer(d)
Commented by cortano12 last updated on 13/Nov/23
minimum 2 red balls between two   adjacent black balls sir.  it′s possible 3 red balls between two   adjacent black balls?
minimum2redballsbetweentwoadjacentblackballssir.itspossible3redballsbetweentwoadjacentblackballs?
Commented by mr W last updated on 13/Nov/23
no,  2, 3, 4 or 5 black balls between  two red balls as the question requests.
no,2,3,4or5blackballsbetweentworedballsasthequestionrequests.
Commented by cortano12 last updated on 13/Nov/23
l got the answer A
lgottheanswerA
Commented by cortano12 last updated on 13/Nov/23
Commented by mr W last updated on 13/Nov/23
yes, you are right! (A) is correct.
yes,youareright!(A)iscorrect.
Answered by MM42 last updated on 13/Nov/23
for“ red” → 2  for “black”  5,2,2→3  /  4,3,2→6  / 3,3,3→1⇒10  ans=2×10×9!=180×8!  ✓
forred2forblack5,2,23/4,3,26/3,3,3110ans=2×10×9!=180×8!
Commented by MM42 last updated on 13/Nov/23

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