The mean weight of 80 students in a class is 60 kg
The mean weight of boys is 70 kg while that of the
girls is 50 kg. the number of boys and girls
are
Answers
Answer:
The mean weight of the boys from the class is 70 kg, while that of girls is 55 kg. What is the number of girls in the class? Now, mean weight of all boys from the class is 70 kg and mean weight of all girls from the class is 55 kg.
Answer:
40,40
Step-by-step explanation:
Total students in class = 80
mean weight=60kg
total weight =80×60=4800kg
Let the total number of boys =x
mean weight of boys =70kg
total weight of boys = 70x kg
total number of girls = total students - no. of boys =80−x
mean weight of girls=50kg
total weight of girls =50×(80−x)
=50×80−50x
= (4000−50x) kg
Total weight = weight of boys + weight of girls
4800=70x+(4000−50x)
4800=70x+4000−50x
4800−4000=70x−50x
800=20x
800/20=x
40=x
So number of boys =40
number of girls =80−40=40
Answer is 40,40