You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

Look at the picture and find out which square is not linked with any of the other squares.

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

Alpha is Beta's sister.

Gamma is a Beta mother.

Delta is Gamma's father.

Tango is Delta's mother.

Then,

How is Alpha related to Delta?

Find the next number in the series below

21 32 54 87 131 ?

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

Why are all black people so quick ?

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

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.
How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?