A larger percentage of the boys picked piano. First you want to add the total number of girls so 12+8=20. Then find the percentage by diving the number of girls that picked piano,12, by the total number of girls, 12/20=.6 then multiply that number by 100. 60 % of girls picked piano. Do the same thing for the boys, 8+4=12, then 8/12=.66666… multiply that by 100 and you get around 66.6 % of boys that picked piano. 66.6 is greater than 60 so a larger percent of the boys picked piano.