Authors:

Arithmetic is where the answer is right and everything is nice and you can look out of the window and see the blue sky - or the answer is wrong and you have to start over and try again and see how it comes out this time.

Carl Sandburg, Frances Schoonmaker Bolin (1995). “Carl Sandburg”, p.17, Sterling Publishing Company, Inc.
Arithmetic is where the answer is right and everything is nice and you can look out of the window and see the blue sky - or the answer is wrong and you have to start over and try again and see how it comes out this time.