130 ×60= 630÷30= 900 ÷30 =
580×0= 45 ×20 = 8 ×108=
25 ×80= 720 ÷80 = 99 ×71≈
352 ÷60≈
1﹣+= 1÷×= 0.5﹣+0.5﹣=
8.1+= (+)×24= 7××7÷=
16÷20%= 4.8÷(0.4+1.2)=
-(-)= 12÷0.25÷4=