Search for texts written by David A. Bell or Denton J. Dailey on Amazon.
I believe they are no longer in print, however you can purchase previous editions of their texts for a fraction of the cost of current editions.
Frankly, after examining many current texts utilized in university classes, both Bell and Dailey's texts present the material in a much better fashion.
Bell's texts typically provide several real world examples of component selection and design.
He also was known for his texts on Operational Amplifiers, which in my opinion have only been equaled or surpassed by a few more recent texts.
As far as the math requirements, typically the basics of electronic design can be adequately covered by a knowledge of multiplication, division, addition, subtraction and the ability to rearrange equations to find unknowns.
BigDog