A maths symbol is hidden in the below Bar Graph. Can you decipher it?

what does this picture(rebus) riddle means ?

What has one letter and starts with an E?

The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.

Boxes are labeled but all labels are wrong!

You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball.

How many such operations are necessary to correctly label the boxes?

Using mathematical symbols like +, -, and x in order to make the equations correct. Replace # with the above-given symbols.

9 # 8 # 7 # 6 # 5 # 4 = 91

If in a car race, the man who came two places in front of the last man finished one ahead of the man who came fifth, how many contestants were there?

Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?

If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

What two things can you never eat for breakfast?

How can you take 2 from 5 and leave 4?