Elementary Mathematics Questions and Answers

The present age of father and son are in the ratio 3: 1. After 20 years the ratio becomes 2 : 1 . Find the present age of the father. 

The present age of A and B are in the ratio 5: 4. After 10 years the ratio becomes 7: 6. Find the present age of A.

The multiplication of the age of Rajeev, before 5 years and after 9 years, is 15. What is the present age of Rajeev?

A pipe can fill a tank in x hours and an another can empty it in y hours. In how many hours will they together fill it. If y>x?

20 buckets of water fill a tank when the capacity of each bucket is 14.5 litres. How many buckets will be required to fill the same tank if the capacity of each bucket is 10 litres?

Two pipes, A and B, can fill a tank in X minutes and 6 minutes, respectively. If both the pipes are used together, then they take 1.5 minute to fill the tank. Find the value of X.

A man can swim at the rate of 3 km/hr. in still water. Then, if speed of the stream is 2 km/hr., then in what time he will cover a total distance of 5 km in with the stream and against the stream?

A boat running upstream takes 7 hours and 40 minutes to cover a certain distance while it takes 5 hours to cover the same distance downstream. What is the ratio between the speed of the current and speed of the boat respectively? 

A boat covers 48 km. upstream and 72 km. downstream in 12 hours, while it covers 72 km. upstream and 48 km. downstream is 13 hours. The speed of stream is -

LCM of two numbers is 2079 and their HCF is 27. If one of the numbers is 189, the other number is