Cambridge mathematics direct 4 numbers and the number system solutions 
Jane Crowden; et al 
 - Cambridge  Cambridge University Press  2000 
 - 24 p. ; 30 cm 
<br/><br/><label>ISBN: </label>9780521798259 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Arithmetic -- Study and teaching (Elementary)
<br/><br/><label>Dewey Class. No.: </label>500 NUM