数学认识钟表ppt课件.ppt
:, . - . -,: , :1. .2. .3. ., : 60 . : ,7-: ,10,20,25,30,35,40,45,50,55,60, ( ) ( ) .,5,9,9:05, ( ) ( ) .,6,25,6:25, ( ) ( ) .,12,12,12:00, ( ) ( ) ., ( ) ( ) .,12,6,12,1, ( ) ( ) .,12,30,12:30, ( ) ( ) ., ( ) .,12,1,1,1 =60,1:00, ( ) ( ) .,4,15,4:15,(16),(16),(18),(19),(17),