There are 14 boys in a class and 16 girls. The Mean height of the class is 1.6m, the mean of the girls is 1.5m what is the mean height of the boys?
Mean for all students: (the sum of all the heights)/total number of students = (the sum of boys+sum of girls)/30 = 1.6sum of boys and girls = 1.6 x 30Mean for girls: (the sum of all the girls' heights)/total number of girls = (the sum of all the girls' heights)/16 = 1.5sum of girls = 1.5 x 16Mean for boys: (the sum of all the boys' heights)/total number of boys = (the sum of all the boys' heights)/14 = ?sum of boys = (sum of boys and girls) - (sum of girls)(1.6 x 30) - (1.5 x 16) = 48- 24 = 24mean for boys = 24/14 = 1.7m
CJ
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