Permutations of UNIVERSAL

76 Views Asked by At

In how many of permutations of word UNIVERSAL, no two of the letters E, R, S occur together.

I'm confused while proceeding with this one, I know total permutation is 9!.

1

There are 1 best solutions below

0
On

The task to arrange the letters can be performed by

  • Permuting the six letters UNIVAL.
  • Permuting the three letters ERS.
  • Merging the second string into the first by selecting three spaces from the seven between (and around) those of first string.
    • thusly each letter of the second string will be separated by at least one letter in the first.

...count the ways...