A toy is formed by placing a solid circular cone on a solid hemisphere and the radius of the common base of the cone and the hemisphere is 15 cm. If the volume of the toy is 2850π cm3, then find the total surface area of that toy.
The following table shows the total number of students in four different classes of a school, and the percentages of students participating in Music or Plays from each of these four different classes. NO student participates both in Music and in Plays.
| Classes | Total number of students in each class | Percentage of participants | |
| Music | Plays | ||
| X | 600 | 12 | 8 |
| IX | 400 | 10 | 6 |
| VIII | 280 | 30 | 15 |
| VII | 250 | 10 | 12 |
What is the total number of students who do NOT participate in Music or Plays from classes X and VII, taken together?
The compound interest earned by Sunil on a certain sum at the end of two years at the rate of 16% p.a., when interest is compounded annually, was ₹864. What was the sum invested by Sunil?