Question

in a class of 60 students there are 30 girls. the average weight of this girl is 58 kg and average weight of the full class is 63 kg. what is the average weight of the boys in the class?​

Answer 1

Data given: Total number of students in class = 60 Number of girls = 30 Average weight of girls = 58 kg Average weight of the whole class = 63 kgSolution:From the given data we can calculate, Number of boys in class = 60 - 30 = 30 (Total number of students - Number of girls)From the given Average weight of girls we can calculate, Total weight of girls = 58 x 30 = 1740 kg(Average weight x Total number of girls)Similarly Total weight of full class = 63 x 60 = 3780 kg(Average weight x Total number of students in class)From above we can calculate, Total weight of boys = 3780 - 1740 = 2040 kg(Total weight of full class - Total weight of girls)From the total weight of boys, we can calculate, Average weight of boys = 2040/30 = 68 kg(Total weight of boys/ Number of boys in the class)Answer is option 3