A boat running upstream takes ^@ 5{\space} hours^@ ^@24{\space} minutes^@ to cover a certain distance, while it takes ^@4{\space} hours^@ to cover the same distance in running downstream. What is the ratio between the speed of the boat and the speed of stream?
The sum of the first 6 terms of an arithmetic progression is 156. The ratio of term 10th to term 30th of the AP is 39:119. What is the value of the 78th term of the AP?
Marcela drew the following figure in her mathematics notebook. In which ^@AB^@ and ^@BC^@ are co-initial tangents drawn from an external point ^@A^@ to the circle ^@OB^@ and ^@OC^@ are the radii of the circle. Then what is always true ^@?^@
There are a cylinder and a cone with height, ^@h^@ and radius ^@r^@. There is also a sphere of the same radius. The height, ^@h^@ of the cylinder and the cone is ^@ 3 ^@ times the radius, ^@r^@. If ^@V_1^@ is the volume of the cylinder, ^@V_2^@ is the volume of the cone and ^@V_3^@ is the volume of the sphere, then which of the following is true?