How many permutations of the letters ABCDEFGH
A. Contain ED
- I thought of ED as one letter and the rest as separate.
then there is only one way to make ED = 1! and 7! ways to rearrange them together= 7!
Answer: 7!1!= 5040
I think the same concept can be used for the rest.
E .
- you can count CABED as one word
4!
F. Not possible 0
