# Andy and Roger

Pro Problems > Math > Statisics and Probabilities > Counting Principles## Andy and Roger

Andy picks three letters from his name and arrange them on the table. Roger picks two letters from his name and arrange them. If Roger puts his two letters after Andy’s three letters, how many possible arrangements of five letters are there?

## Solution

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In how many different ways can the letters STOPS be arranged?

### Burgers and Condiments

Burger Heaven is the new restaurant in town, and they offer to make your burger however you want it, with the following possibilities:

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In a basket I have slips of paper with several different digits on them. In another basket I have slips of paper with several different letters on them. If I reach into the first basket and pull out a number, and then reach into the second basket and pull out a letter, there are 161 possible results. How many letters of the alphabet are *not *in the second basket?

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If I have pie, I can choose mince, lemon meringue, cherry, or apple.

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