For the following questions answer them individually
The force of attraction between two objects of masses 'M' and 'm' which lie at a distance 'd' from each other is directly proportional to the-
Ratio of the volumes of a sphere of radius 'r' and a cylinder of radius 'r' and height '2r' is:
Rajan got married 8 years back. His age then was 5/6 of his present age. His sister was 10 years younger at the time of his marriage. How old is she now?
Speed of a boat in still water is 13 km/h. Speed of water current is 4 km/h. In what time can the boat cover 68 km upstream?
Find the smallest among these fractions.
$$\frac{1}{2}$$ ,$$\frac{3}{5}$$, $$\frac{2}{7}$$, $$\frac{5}{6}$$