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In a cycle race there are 5 persons participated for 5 positions named as J,K,L,M,N.
So that in how many number of ways can make M always before N?
Read Solution (Total 19)
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- m is always before n
it means not only beside may be like this
3! is for arranging jkl
m---- 4 positions for n so 4(3!)
-m--- 3 positions for n so 3(3!)
--m-- 2 positions for n so 2(3!)
---m- 1 position for n so 1(3!)
so 3!(1+2+3+4)=60 ways - 10 years agoHelpfull: Yes(43) No(3)
- 4! = 24 ans
- 10 years agoHelpfull: Yes(29) No(32)
- m and n taken as one unit then put this one unit in 5 places = 5C2=10
now in remaing 3 palces, put j k l as 3!=6
no of ways= 6*10= 60 ways - 10 years agoHelpfull: Yes(20) No(5)
- j,k,l,(m,n)=4!=24
- 10 years agoHelpfull: Yes(12) No(10)
- Say M came first. The remaining 4 positions can be filled in 4! = 24 ways.
Now M came in second. N can finish the race in 3rd, 4th or 5th position. So total ways are 3 x 3! = 18.
M came in third. N can finish the race in 2 positions. 2 x 3! = 12.
M came in second. N can finish in only one way. 1 x 3! = 6
Total ways are 24 + 18 + 12 + 6 = 60. - 7 years agoHelpfull: Yes(12) No(0)
-M--- =3p1*3p3+
--M--=3p2*2p2+
---M=3p3*1
24+(3*6)+(6*2)+6==24+18+12+6=60
- 10 years agoHelpfull: Yes(7) No(1)
- omg..santy...!!!!
galat ans diya. - 10 years agoHelpfull: Yes(5) No(2)
- positions -----
m---- = 4 ways for n
-m--- = 3 ways for n
--m-- = 2 ways for n
---m- = 1 way for n
ans 10 ways - 10 years agoHelpfull: Yes(4) No(8)
- Say M came first. The remaining 4 positions can be filled in 4! = 24 ways.
Now M came in second. N can finish the race in 3rd, 4th or 5th position. So total ways are 3 x 3! = 18.
M came in third. N can finish the race in 2 positions. 2 x 3! = 12.
M came in second. N can finish in only one way. 1 x 3! = 6
Total ways are 24 + 18 + 12 + 6 = 60.
Shortcut:
Total ways of finishing the race = 5! = 120. Of which, M comes before N in half of the races, N comes before M in half of the races. So 120 / 2 = 60. - 6 years agoHelpfull: Yes(3) No(0)
- Total number of ways in which 5 persons can finish is 5! = 120 (there are no ties)
Now, in half of these ways M can finish before N.
so ans is : 60 ways,,,,,, - 5 years agoHelpfull: Yes(3) No(0)
- ----N 4 ways for M
---N- 3 ways for M
--N-- 2 ways for M
-N--- 1 ways for M
total=10 ways - 10 years agoHelpfull: Yes(2) No(4)
- If M came first. The remaining 4 positions can be filled in 4! = 24 ways.
Now M came in second. N can finish the race in 3rd, 4th or 5th position. So total ways are 3 x 3! = 18.
M came in third. N can finish the race in 2 positions. 2 x 3! = 12.
M came in second. N can finish in only one way. 1 x 3! = 6
Total ways are 24 + 18 + 12 + 6 = 60. - 7 years agoHelpfull: Yes(2) No(0)
- 4!=24 ways
- 10 years agoHelpfull: Yes(1) No(2)
- Here,M have always comes before n.So take it as one unit.
If we take two letters from the set,we get 3 letters(5-2 = 3)
these 3 units + above one unit(M before N) = 4
These 4 units can be arranged in 4! ways
4! = 24 ways.
Therefore,we can arrange them in 24 ways - 5 years agoHelpfull: Yes(1) No(0)
- 6!= 720 ans
- 10 years agoHelpfull: Yes(0) No(3)
- 4+3+2+1 = 10
- 10 years agoHelpfull: Yes(0) No(3)
- 78 ways:
----N =4!=24
---N-=3!*3!=36
--N-- =2!*3!=12
MN--- =3!=6
--- - 10 years agoHelpfull: Yes(0) No(3)
- J K L M N
1 Condition is M > N,
thus N always loose the game by last.
so answer is 4* 5c4 = 20 - 10 years agoHelpfull: Yes(0) No(3)
- Ans: 60
Sol: Total number of ways in which 5 persons can finish is 5! = 120 (there are no ties)
Now in half of these ways M can finish before N. - 6 years agoHelpfull: Yes(0) No(3)
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