If the average marks of three classes of 60, 65 and 70 students are 60, 65, 70 respectively, find the average marks of all the students (Approximately)
1
69.2566666litres are drawn from a cask full of wine and is then filled with water. This operation isperformed once more. The ratio of the quantity of wine now left in cask to that of thewater is 16:9. How much wine does the cask hold originally? (In liters)
2
67.25
3
71.25
4
65.25