What is in seasons, seconds, centuries and minutes but not in decades, years or days?

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?

Christina is practising her dance steps along with her friends. In a particular sequence, all of them form a row. At that point, Niharika is standing in the 4th position from either end of the row.
Can you find out how many girls are practising together?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

Find the missing number in the sequence below:

In the attached figure, you can see a chessboard and two rooks placed on the chess board. What you have to find is the number of squares that do not contain the rooks. How many are there?

How many triangles are there in the picture below?

What is the next shape from answers A, B, C, and D figure?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?