Question

Ana, Bill, and Charles are getting ready to pose for a photograph. How many different ways could they line up for the picture so that Ana and Bill are standing next to each other?

Answer 1

The answer is 6 based on probability but answer is 4 on apex hope this helps

Answer 2

There are two ways of Anna-Bill standing next to each other when Anna is on the left side of Bill. See below.
$\boxed{AB}C$
$C\boxed{AB}$

There are two ways of Bill-Anna standing next to each other when Bill is on the left side of Anna. See below.
$\boxed{BA}C$
$C\boxed{BA}$

There are 4 different ways