The number of ways in which 10 different flowers can be strung to form a garland.So that 4 particular flowers are never separated.
8460
8640
8480
6840
If nCr denotes the number of combinations of n things taken r at a time,then the expression n(r+1+n(r-1)+2*nCr equals
n+1Cr+1
n+2Cr
n+2Cr+1
n+1Cr
In how many ways 6 gentlemen and 3 ladies can be seated round a table So that every gentleman may have a lady by his side.
720
1440
1880
1040
The number of ways in which n different beads can be arranged to form necklace are
(n+1)!
n!
(n-1)!/2
(n+1)!/2
If 43 Cr-6 = 43C3r+1,then the value of r is
12
8
6
10
If (n+1)! = 56 (n-1)!,then n=
7
9
If nc4 = nc6,then the n=
2
In how many ways can 7 persons sit around a table.So that all shall not have the same neighbours in any two arrangements?
180
260
360
How many numbers can be formed with digits 1,2,3,4,3,2,1 .So that odd digits always occupy the odd places?
18
20
24
If nc10 = nc14,then 25 Cn =
25
25!
24!
