Can you solve this tricky maths equation problem by replacing it? mark with the correct symbol?

19834 -----: 187
15921 -----: 153
17561 -----: 139
13734 -----: ???

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

Count the number of triangles in the picture below:

A girl has as many brothers as sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?

Can you solve the maths in the below-given picture equation?

These types of puzzles are known as charades. What you have to do is to find two words that are referred to in the first stanza and the second stanza and put them together to form the third word in the third stanza.

Just for example, if my first refers to 'off' and my second refers to 'ice', then my whole will be the 'office'.

My first is present - future's past -
A time in which your lot is cast.

My second is my first of space
Defining people's present place.

My whole describes a lack of site -
A place without length, breadth, or height.