There are 25 boy students and 20 girls students in a school. The average of marks in math of 25 boy students is 52 and the average of marks in math of 20 girl-students is 48. Find the average of marks obtained by the students of the school as a whole.

Explanation

Here `n_(1)=25 and n_(2)=48`.
`barx_(1) =52 and barx_(2)` =48
`therefore ` the collective average
`barx=(n_(1)barx_(1)+n_(2)barx_(2))/(n_(1)+n_(2))=(25xx52xx20xx48)/(25+20)`
`=(1300+960)/(45)=(2260)/(45)=50.2 ` (approx.)