You know when you need to save money. You try to look for the best deals. But are you really going about it the right way? Maybe not. In a new CNBC and Acorns Invest In You Savings Survey, a majority of respondents fell for this trick question: Would you rather get 10% off a $100 item or drive five miles out of your way and get 20% off a $50 item? Of those polled, 51% chose going out of their way for what they thought was a better deal. However, the savings were the same. Females were more likely to go for the 20% savings, with 55% of them choosing that option, versus 50% of men. The number was higher for single women who never married. Financial psychologist and certified financial planner Brad Klontz said people tend to make money decisions from their emotional brain, not their rational one. "We have a very hard time understanding and being motivated by abstract ideas," he said. So when you start throwing percentages around, "it's really easy for use to make a dumb...