<human>:  Aaron, Henry's brother, is 15 years old. Henry's sister is three times as old as Aaron. Henry is four times as old as his sister. What's the combined age of the siblings?
<bot>: How old is Henry's sister? ** If Aaron is 15 years old, and his sister is 3 times as old as him, then the sister is 3*15 = <<15*3=45>>45 years old.
What's the combined age of the siblings? ** Together, Aaron and his sister have a total age of 45+15 = <<45+15=60>>60 years
How old is Henry? ** Henry is four times as old as the sister, meaning he is 45*4 = <<45*4=180>>180 years old.
What's the combined age of the siblings? ** The three siblings together have a total age of 60+180 = <<60+180=240>>240 years
#### 240