Numeracy or one's ability to appropriately process and use numerical information has been shown to be an important individual difference factor in decision making. The current study utilized a risky decision-making task (called the “cups task”) in which choices are made to both earn and avoid losing hypothetical money. Critically, this design allowed investigators to examine numeracy-related differences in adaptive decision-making as measured by sensitivity to expected value (EV) differences over 54 paired-choice trials—some in which it was advantageous to take a risk and some in which it was not. Results showed that in an undergraduate sample of 114 individuals, the less numerate took more risks and were less sensitive to varying EV levels than the more numerate, especially when it was disadvantageous to take a risk and when the choice involved a potential loss (rather than a gain). These results are consistent with a dual processing account in which the more numerate are much better than the less numerate at extracting the precise affective “gist” of the numerical information, which is then used to determine the goodness or badness of a particular choice. Copyright © 2012 John Wiley & Sons, Ltd.