Stocks jumped Friday following a better-than-expected rise in profits at Research in Motion Ltd. and on word that Merrill Lynch may have lined up a big cash infusion from a Singapore fund.

The Dow Jones industrial average capped a volatile week with a gain of more than 200 points and, along with the other major indexes, posted an increase of more than 1.5 percent.

The developments seemed to allay investor fears that economic growth would succumb to tightness in the credit markets.

The Dow rose 205.01, or 1.55 percent, to 13,450.65.

Broader stock indicators also showed strong gains. The Standard & Poor’s 500 index rose 24.34, or 1.67 percent, to 1,484.46, and the Nasdaq composite index advanced 51.13, or 1.94 percent, to 2,691.99.