How many ways can you write two different letters chosen from

A B C D E F G H I J K L M N O P

so that they are in alphabetical order, and the first letter is a vowel? For example, AF and EN count, but DE and KC do not.

wiseowl Feb 19, 2024

#1**+1 **

*How many ways can you write two different letters chosen from A B C D E F G H I J K L M N O P so that they are in alphabetical order, and the first letter is a vowel?*

two different letters

in alphabetical order

the first letter is a vowel

If the first letter is A, then there are **15** possibilities. (Second letter can be anything past A.)

If the first letter is E, then there are **11** possibilities. (Second letter can be anything past E.)

If the first letter is I, then there are **7** possibilities. (Second letter can be anything past I.)

If the first letter is O, then there is **1** possibility. (Second letter can be only P.)

Add them up. **34** possibilities.

_{.}

Bosco Feb 19, 2024