the method is (the students prefer juice/the total number of students)*100%
for grade7: [(11+13+20)/(12+19+11+13+20+5)]*100% =(44/80)*100% =55% For grade8: [(13+27+4)/(20+12+13+27+4+8)]*100% =(44/84)*100% =52.38% 55%>52.38% Therefore the answer is grade 7
