The ratio of the volume of two cylinders is 7 : 3 and the ratio of their heights is 7 : 9. If the area of the base of the second cylinder is 154 sq. cm, then what will be the radius (in cm) of the first cylinder?
4. In triangle PQR, the sides PQ and PR are produced to A and B respectively. The bisectors of ?AQR and ?BRQ intersect at point O. If ?QOR = 50°, then what is the value (in degrees) of ?QPR?
6. In triangle ABC, AD, BE and CF are the medians intersecting at point G and area of triangle ABC is 156 sq.cm. What is the area (in sq.cm) of triangle FGE?
7. The length of diagonal of a square is 9?2 cm. The square is reshaped to form a triangle. What is the area (in sq.cm) of largest in circle that can be formed in that triangle?
8. If the radius of the cylinder is increased by 25%, then by how much percent the height must be reduced, so that the volume of the cylinder remains same?