They Spoke to Me

mountain (of) bikes

[Photo ©2012 William Bosch, Shantou, Guangdong Province, China]

An example of addition outside a school in China. Subtraction comes later (in the afternoon.)

(Larger photos, 2x, available here https://williamboschdotcom.files.wordpress.com/2012/10/bksstckschlshntchn1000.jpg)