Math help

To assist you with the basic math concepts I have created the adjacent "Introductory Math Concepts for Ultrasound Physics" video.

Additionally,  you can check out the math video tutorials at the Khan Academy.  Here's one on unit conversion, for example.  Their site is searchable, so you should be able to find videos on just about all mathematical concepts.

The Khan Academy is a not-for-profit educational organization created by Salman Khan. With the stated mission of "providing a high-quality education to anyone, anywhere", the website supplies a free online collection of over 2,200 micro lectures via video tutorials stored on YouTube teaching mathematics, history, finance, physics, chemistry, biology, astronomy, and economics.