一、口算。
$64 - 27 =$ $6×9 =$ $45÷5 =$
$5×8 =$ $26 + 44 =$ $27÷3 =$
$70 - 39 =$ $7×4 =$ $58÷6 =$
$3×6 =$ $85 - 49 =$ $27÷4 =$
$32 + 29 =$ $5×2 =$ $14÷2 =$
$7×8 =$ $65 - 28 =$ $30÷4 =$
$53 + 28 =$ $5×6 =$ $55÷6 =$
$3×4 =$ $95 - 76 =$ $42÷8 =$
$87 - 59 =$ $4×5 =$ $35÷9 =$
$9×8 =$ $24 + 49 =$ $48÷7 =$

一、37 54 9
40 70 9
31 28 9……4
18 36 6……3
61 10 7
56 37 7……2
81 30 9……1
12 19 5……2
28 20 3……8
72 73 6……6

二、单位换算。
$300$厘米$=($ $)$米 $0.5$米$=($ $)$厘米
$110$厘米$=($ $)$米 $1.25$米$=($ $)$厘米
$3$米$20$厘米$=($ $)$米 $20$厘米$+($ $)$厘米$=1$米
$2.05$米$=($ $)$厘米 $22$厘米$+38$厘米$=($ $)$米
$2.08$米$=($ $)$米$($ $)$厘米 $($ $)$厘米$+35$厘米$=0.8$米

二、3 50
1.1 125
3.2 80
205 0.6
2 8 45