Genuineness of Assent

Sam wants to sell his stereo system because one side of his amplifier occasionally doesn't work properly and the cost of repair is so high that Sam wants to get a new stereo.Otherwise, it works well and the sound quality is very good.Sam places an advertisement in the newspaper and Bob comes to look at it.Bob tries it out and likes what he hears.The following conversation then takes place:

Bob:How does it work?

Sam:Listen for yourself.Isn't that sound great?

Bob:Yes it is.Have you ever had to have it repaired?

Sam:It's never been repaired ... it's just as it came from the factory.Try the CD, the cassette tape and the tuner.You'll see they all work.

Bob spends an hour or so playing and testing the stereo system.Sam and Bob then negotiate a price.Bob pays and takes the stereo home only to discover the problem.Bob wants to get out of the contract.Discuss whether Bob can get out of the contract and get his money back.