第 11 课时 练 习 课,1.算一算,比一比8+4+7= 13-6+3=8+(4+7)= 13-(6+3)=,19,19,10,4,2.算一算 5+(2+3)= 7+(14-9)=40+20+8= 90-(16+4)=,10,12,68,70,方法1:45-5-3=37(箱),方法2:45-(5+3)=37(箱),4.算一算 54-5+30= 76-6-8=87-9-10= 65-7-40=43-(3+27)= 39-(9-5)=,79,62,68,18,13,35,8,19,35,16,28,41,33,82,76,63,73,89,64,33,(1)7240=32(人) (2)已经检查的人中,有多少人没有近视?,15,78,30,38,37,56,47,