This is a budget related post because DD just called me from college in a panic. Her math book for this semester was $245
. I found what I think is the same book on Amazon for $189 (still expensive, but a huge savings). How do I know it's the same book with the same online access? I checked the isbn number so that should be OK, right? Reassure me, because I am horrified at these prices for a one semester book. 

