An artist while painting a scenic beauty, decides to paint three layers of blue colour on the sky.

Which layer will go on the first?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

We have arranged an array of numbers below. What you have to do is use any kind of mathematical symbol you know excluding any symbol that contains a number like cube root. You can use any amount of symbols but you have to come up with a valid equation for all of them.

0 0 0 = 6
1 1 1 = 6
2 + 2 + 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

What is next number in the pattern below:

131 517 192 123 ?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

I get hot but I never sweat,
I cook food but I am not a chef,
I have a door but you can't enter me,
I have a light but I am not a lamp.
Who am I?

You need to move three matchsticks to form three squares. Can you do it?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M