How do you put a price on the tangible-asset value of a company?

I’m reading The Intelligent Investor currently and it says that “it might be best for him to concentrate on issues selling at a reasonably close approximation to their tangible asset value-say, at not more than one-third above that figure”. My question is how do you convert the tangible assets to a price? Is there a specific price per dollar of tangible assets? Is this claim still reasonable with today’s market prices?