Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

How many triangles are there in the picture below?

There is one four-digit whole number n, such that the last four digits of n2 are the original number n

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

In a town, there are four houses located at different distances from each other. Following are the distances:

The third house is 60 meters apart from the first house.
The fourth house is 40 meters apart from the second house.
The third house is 10 meters nearer to the fourth house than it is to the second house.

Can you find out the distance between the fourth and the first house?

Our product and our sum always give the same answer. Who are we?

Find out the missing number in the picture attached:

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

What number divided by 4 is the same as that number minus 4?