That is correct. Floating point numbers are approximations. Just as 0.33333333 is an approximation to 1/3, 56.7999999 is an approximation for 56.8. There is no exact floating point representation for 0.1.
See some of what has been written:
- http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
- http://www.hack3r.com/forum-topic/what-every-programmer-should-know-about-floating-point-arithmetic
