The average score of class P, Q & R are 76 , 63 , 95 . The ratio of number of students in three classes is 27 , 36 and 45 respectively. Find the combined average of the all three classes ( approx ).
Answer & explanation
Correct answer: option 3
P : Q : R
Ratio No. of students 27 : 36 : 45
3 : 4 : 5
Average 76 63 95
Total Sum 228 252 475
Average of P, Q & R (combined) = \(\frac{228 + 252 + 475}{12}\) = 79.58