what does this picture(rebus) riddle means ?

What does the below rebus riddle means?

Can you count the number of children in the picture below

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

Only one color, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Which word does the below Plexor means ?

What does does this rebus picture means ?

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognises the three as friends and asks the waiter to return $5 to the men.

The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.

Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14. Where has the other $1 gone from the original $15?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

What happened when the wheel was invented?