A vertical stick which is 36cm long casts a 33cm long shadow on the ground. At the same time, a vertical tower casts a 70m long shadow on the ground. Find the height of the tower.
The perimeters of the ends of the frustum of a cone are 7.48cm and 9.24cm. If the height of the frustum is 28cm, find its curved surface area. (Take π=227).
A bag contains 6 red balls, 4 blue balls and 5 green balls. Richard draws 2 balls out of the bag. What is the probability that he gets a red ball and a blue ball?
In this diagram, the triangle represents men, the square represents teachers and the circle represents tall. Find the number of men who are tall but not teachers.