If 21x = 79x, what is the value of x?

Can you find the 09 errors in the picture below?

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

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

What is the next number?

77, 49, 36, 18 ?

Can you find out the next digit in the following series ?

0, 0, 1, 3, 2, 6, 3, 9, 4, 12, 5, ?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

On rolling two dices (six-sided normal dice) together, what is the probability that the first one comes up with a 2 and the second one comes up with a 5?

You have a roll of cloth 1km long. You have a machine which cuts this roll into pieces of 10-meter-long cloth.

How long would it take for the machine to cut the roll if each cut took 4 secs?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?