Question
The radius of the base of a
cylindrical tank is 5 metres. If eight times the sum of the areas of its two circular faces is four times the area of its curved surface, then find the difference between its radius and its height. {Take π = 22/7}Solution
ATQ,
Area of two circular faces = 2πr2 Curved surface area (CSA) = 2πrh Equation = 8×(2πr2) = 4×(2πrh)
Simplify: 16πr2 = 8πrh ⟹ 2r = h Substitute r = 5: h = 2r = 2×5 = 10metres Find the difference = h − r = 10 − 5 = 5metres
What will come in place of the question mark (?) in the following series?
11, 18, 32, 60, ?, 228What will come in place of the question mark (?) in the following series?
1.5, 3.5, 9.5, 27.5, 81.5, 243.5, ?
14    36    80    168    ?     696
24, 168, 28, 140, 35, ?Â
7, 6, 10, 27, 104, ?Â
84, 97, ?, 162, 214, 279
6400, 1600, ?, 80, 16, 4
31    32      35      ?      47       56
...What value should come in the place of (?) in the following number series?
64, 80, 104, ?, 176, 224
1140, ?, 1130, 1160, 1120, 1170
