#### Answer

288,864,576

#### Work Step by Step

Use the conversion factor that relates seats to tricycle. Arrange it so the tricycle cancels out and we're left with how many seats required
Use the conversion factor that relates wheels to tricycle. Arrange it so the tricycle cancels out and we're left with how many wheels required
Use the conversion factor that relates pedals to tricycle. Arrange it so the tricycle cancels out and we're left with how many pedals required.