一年级下册《练习十七》 ppt课件.ppt
练习十七,1. 算一算,比一比。,8 + 4 + 7 = 13 - 6 + 3 = 8 +(4 + 7)= 13 -(6 + 3)=,19,19,10,4,2.,5 +(2 + 3)= 7 +(14 - 9)= 40 + 20 + 8 = 90 -(16 + 4)=,10,68,12,70,45-5-3=,45-(5+3)=,37(箱),37(箱),54 - 5 + 30 = 76 - 6 - 8 = 87 - 9 - 10 = 65 - 7 - 40 = 43 -(3 + 27)= 39 -(9 - 5)=,79,68,62,18,4.,13,35,5.,8,19,35,16,28,41,6.,33,82,76,63,33,64,89,73,72-40=32(人),已经检查了的人中,有多少人不是近视?,40-6=34(人),8.,36 + 40 + 2 = 59 - 9 - 20 = 63 - 30 + 5 = 30 +(11 - 4)= 47 +(18 - 9)= 40 +(15 - 8)=75 -(10 + 50)=,78,30,38,37,56,47,15,=,53,8,26,76,56,56,82,70,