Transposition made easy 2

Here's another simple transposition video. Such techniques may be applied to all chemistry and physics courses. :)

[thesciencehubskb]

There's a mistake at the end where I said = ef it should be = e/f Sigh. Sorry.

[ilutables]

hi can you please help me transpose the following equation for 'r' in terms of v and u: 1/v + 1/u = 2/r