what would be the first step into solving this problem?

For three fast-food restaurants, Mcdonald, El Pollo Loco, and Subway, eighteen years of customer satisfaction scores were collected. The following three histograms summarize those data. McDonald Consumer Satisfaction El Pollo Loco Consumer Satisfaction Subways Consumer Satisfaction Frequency Frequency Frequency N. 50 55 60 65 70 75 80 50 55 60 65 70 75 80 50 55 60 65 70 75 80 FastFoodSMeDonald FastFoodSE PotoLoco FastFoodsSubways Based on the histograms provided, which fast-food restaurant do you believe consistently has the highest customer satisfaction scores? Explain why