1. In a class of 40 students, 25 are boys. The
average mark of boys is 36 and that of the girls is 40.
What is the average mark of the class?
Answers
Answer:
Step-by-step explanation:
Heya,
Given:-
Total no.of students = 40
Total no.of boys = 15
Total no. of girls = 40-15 = 25
Mean marks of boys = 33
Mean mark of girls = 35
To find:-
Mean of all students
Solution:-
Let's assume,
Sum of marks of boys = x
Sum of marks of girls = y
Therefore,
x/Total boys = 33 (mean)
x/15 = 33
× = 33 × 15
x = 495
y/Total girls = 35 (mean)
y/25 = 35
y = 25 × 35
y = 875
=> Total marks by all = x + y
=> Total marks by all = 495 + 875
=> Total marks by all = 1370
Therefore,
Mean of all students = Total mark/Total students
Mean of all students = 1370/40
Mean of all students = 137/4
Mean of all students = 34.25
Hope my answer helps you :)
Answer:
Step-by-step explanation:
Heya,
Given:-
Total no.of students = 40
Total no.of boys = 15
Total no. of girls = 40-15 = 25
Mean marks of boys = 33
Mean mark of girls = 35
To find:-
Mean of all students
Solution:-
Let's assume,
Sum of marks of boys = x
Sum of marks of girls = y
Therefore,
x/Total boys = 33 (mean)
x/15 = 33
× = 33 × 15
x = 495
y/Total girls = 35 (mean)
y/25 = 35
y = 25 × 35
y = 875
=> Total marks by all = x + y
=> Total marks by all = 495 + 875
=> Total marks by all = 1370
Therefore,
Mean of all students = Total mark/Total students
Mean of all students = 1370/40
Mean of all students = 137/4
Mean of all students = 34.25
Hope my answer helps you :)
Regards,