Which of the following represents a correct proportion?

Speed of a man in still water is 15 kmph , while river is flowing with a speed of 3 kmph and time taken to cover a certain distance upstream is 3 hours more than time taken to cover the same distance downstream . Find the distance.

The ratio of the ages of two persons is 4 : 7 and the age of one of them is greater than that of the other by 30 years. The sum of their ages ( in years ) is 

Sum and product of two numbers is 11 and 18 respectively. What will be the sum of their reciprocals? 

If A exceeds B by 40%, B is less than C by   20% , then A:C is

If 1,000 is divided into three parts in the ratio 2 : 3 : 5, find the value of the smallest part.

If a : b=2 : 5, b:c=4 : 7 and c : d=9 : 14, then Find out the value of a : b : c : d=?

The population of Jaipur is 20,00,000. If it is increased by 5 %, 10%, 20% respectively in the next three years, then find the population of Jaipur after 3 years.