plz answer all questions

[papakehteyhain]

1. A cylinder, a cone and a sphere have the same surface area. Which has the greatest volume?

a)Sphere b) Cylinder c) c) Cone d) None of these

2. A scalene, Equilateral, Isoceles and right angle triangle are formed with 4 wires of equal length. Which one has greatest area?

a) Scalene b)equilateral c) Isosceles d) None of these

3. The numbe of triangles that can be formed by drawing all the possible diagonals from a single vertex of an n-sided figure is

a) n b) n-1 c) n+1 d) n-2

4)



AD=3, AE=4, DB=9, EC=5 and DE=3.5 find BC =?

a)7 b) 9 c)10.5 d) 10

[riz1983]

1. A (consider the extreme or maximum case in which radii of all the 3 figures are equal. Even then if we calculate the volumes, we have sphere having max volume)

2. B ( Consider a case of wire with length of 12 cm. we can have a right triangle with sides of lengths 3, 4, 5, which is also a scalene triangle => Area = 6.

Equilateral triangle with side = 4 => area = 4(3)^2. which is greater)

3. D ( Always n-2, excluding the vertices immediate next to the chosen vertex)

4. C

triangle ADE and triangle ABC are symmetric. since

AD/AC = AE/AB = DE/BC = 1/3

so 3.5/ BC=1/3

BC = 3.5(3) = 10.5.

please confirm my answers ............. Questions are really good.....