一、口算。
$\mathrm{}$25+53=         9×6=            26÷6=
4×8=            83−47=          30÷4=
56−38=          3×9=            30÷5=
8×5=             52−33=          52÷8=
27+46=            2×6=          40÷7=
7×3=              70−41=           16÷2=
4×3=              43+37=              32÷7=
45−27=             5×5=            48÷8=
6×6=              43+29=            36÷9=
55−28=             5×9=              25÷3=

$25 + 53 = 78$
$9 × 6 = 54$
$26 ÷ 6 = 4······2$
$4 × 8 = 32$
$83 - 47 = 36$
$30 ÷ 4 = 7······2$
$56 - 38 = 18$
$3 × 9 = 27$
$30 ÷ 5 = 6$
$8 × 5 = 40$
$52 - 33 = 19$
$52 ÷ 8 = 6······4$
$27 + 46 = 73$
$2 × 6 = 12$
$40 ÷ 7 = 5······5$
$7 × 3 = 21$
$70 - 41 = 29$
$16 ÷ 2 = 8$
$4 × 3 = 12$
$43 + 37 = 80$
$32 ÷ 7 = 4······4$
$45 - 27 = 18$
$5 × 5 = 25$
$48 ÷ 8 = 6$
$6 × 6 = 36$
$43 + 29 = 72$
$36 ÷ 9 = 4$
$55 - 28 = 27$
$5 × 9 = 45$
$25 ÷ 3 = 8······1$

二、选择合适的答案，在$□$里画“√”。