The number of 6-digit even numbers that can be made from the number 214635 are:

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The number of 6-digit even numbers that can be made from the number 214635 are:  a) 18 b) 72  c) 120 d) 360 Answer:  D from the question we can see we have to form 6 digit number(no repetition) so, let us six blanks as show below : _ _ _ _ _ _  if the number has to be even it has to be end with even number. 214635   from the above digits even numbers are 2,4,6 so, the units digit is 2 or 4 or 6 so, the no.of.ways is 3 remaining 5 digits can be filled with 5! ways  so, the answer is 5!x3 ways                             = 360 ways  remaini
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The number of ways in which 8 different flowers can be strung to form a garland so that 4 particular flowers are never separated are? | cts previous year aptitude questions



 The number of ways in which 8 different flowers can be strung to form a garland so

that 4 particular flowers are never separated are? ( cts previous year aptitude questions )

a) 960

b)2880

c)288

d)576

The number of ways in which 8 different flowers can be strung to form a garland so that 4 particular flowers are never separated are? cts previous year aptitude questions


Answer: D

The concept used is Permutations .

The keyword to be  observed is "garland" i.e , the circular permutations  (n-1)! ways.

8 different flowers can be arranged in 7! ways { (n-1)! }

The 4 flowers never can be separated . let us consider those 4 flowers as a one unit.

now , the total number of ways are 4!

The flowers that are put together can arrange themselves in 4! ways 

So, The total ways are 4!x4! 

24 x 24

576 ways




 


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