Answer:
Going to a mall can influence the money you carry
Explanation:
I think that the question can have two approaches, the first being the question of age, because you may not find many people of that age in a shopping centre.
The second approach, and the one that I think is more accurate, is that when people go to a mall, they are mostly shopping, so they have more money in their pocket than usual, which can alter the data, so it is best to do the survey in a park or in a neighborhood, where people at that time do have the money that they usually have.