(This is a continuation of the series from last year. The first such question is found here)
A party is being held at a local mansion. The host is very rich and his success is because of one thing ~ his famous recipe for Spaghetti!
The only guests that may attend are people the host knows and trusts, whom he gave the password to enter to.
Here's where you come in. You and a friend are trying to steal this recipe. You sneak by and listen to the passwords.
The first guest arrives. The security guard says "5". The guest says "5", and enters the mansion.
The second guest arrives. The security guard says "9". The guest replies "5", and is admitted.
The third guest arrives. The security guard says "3". The guest replies "5", and enters.
Your friend thinks he's got it all figured out. He climbs out of the bushes and approaches the guard. The guard says "4". Your friend confidently says "5". The guard then pulls a lever, opening a trap door beneath your friend. He falls to his death.
The fourth guest arrives. The guard says "6", and the guest replies "24" and enters the party.
At this point you believe you know what's going on. You approach the guard, and he says "7".
What do you say?