Rinko’s mother decides she wants to go to Whole Foods. Rinko, however, declares that she cannot go out unless she wears exactly four leg coverings. Rinko’s mother can choose from silk stockings (three pairs, which cannot be put on top of anything else except another silk stocking), hiking socks (two pairs), and shin guards (two pairs, which cannot be put underneath anything else except another shin guard). In addition, Rinko commands his mother to use at least one of each type of covering. If the same coverings in a different order counts as a different combination, how many combinations of leg coverings can Rinko’s mother wear that will allow her to go to Whole Foods?
Make a list of what you have. eg
Silk stockings, 3 pair, must go on first Call them S
shin guards ....
Hiking socks ....
you finish that.
Now make a list of all possible layers of 4 types. Hint: There is not that many.
Now work out how many ways you can each of those.
Get back to us with what you now manage to do for yourself.