A sum of money of Rs. 1000 is lent out in two parts in such a way that the interest on one part at 10% per annum for 5 years is equal to another at 5% for 10 years. Calculate the sum lent out at 5%.
The mean of marks secured by 60 students in division A of class X is 64, 40 students of division B is 60 and that of 60 students of division C is 58. Find the mean of marks of the students of three divisions of Class X.