If the business's stock price rises 30%, then his share on the company is worth 30% multiplied by $2000 plus $2000 that he already had. That results in 30% * $2000 + $2000 = $600 + $2000 = $<<30*.01*2000+2000=2600>>2600.
Since he already had $300, with $2600 more he will have $300 + $2600 = $<<300+2600=2900>>2900.
#### 2900