Part C - Elementary Mathematics
If the average marks of three sections of Class X, having 35, 40, and 25 students, respectively, are 90, 88, and 80, then the average marks of all the students of Class X, is:
400 custard apples were bought at โน1,200 per hundred and were sold at a profit of โน900. Find the selling price (in โน) per dozen of custard apples.
Find the value of [(26 × 14) × {9 ÷ 3 × (\(\frac{19 - 15}{2}\)}]