Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

There is a jar in which there are two types of candies.
20 blueberries and 16 strawberries. You perform the following steps:
1) You take out two candies.
2) If the two candies are of the same flavour, you add a blueberry one otherwise, you add the strawberry one.

You repeat these two steps till there is just one candy remaining in the jar. Which flavoured candy will be left?

What is the probability of choosing the correct answer at random from the options below?

a) 1/4
b) 1/2
c) 1
d) 1/4

Can you count the number of quadrilaterals in the picture below?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

In the image given, you can find several triangles. Can you count them all?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

Find the next number in the sequence

5 12 24 36 ?