一、口算。
$28 + 48 =$         $4 × 9 =$         $22 ÷ 3 =$
$5 × 7 =$         $44 - 26 =$         $27 ÷ 4 =$
$62 - 28 =$         $5 × 6 =$         $18 ÷ 6 =$
$3 × 4 =$         $32 + 23 =$         $40 ÷ 5 =$
$54 - 28 =$         $2 × 8 =$         $36 ÷ 9 =$
$4 × 5 =$         $72 - 27 =$         $28 ÷ 8 =$
$37 + 28 =$         $2 × 3 =$         $48 ÷ 6 =$
$7 × 8 =$         $90 - 55 =$         $17 ÷ 2 =$
$77 - 55 =$         $8 × 9 =$         $38 ÷ 5 =$
$6 × 7 =$         $36 + 45 =$         $52 ÷ 7 =$

$28 + 48 = 76$；$4 × 9 = 36$；$22 ÷ 3 = 7······1$
$5 × 7 = 35$；$44 - 26 = 18$；$27 ÷ 4 = 6······3$
$62 - 28 = 34$；$5 × 6 = 30$；$18 ÷ 6 = 3$
$3 × 4 = 12$；$32 + 23 = 55$；$40 ÷ 5 = 8$
$54 - 28 = 26$；$2 × 8 = 16$；$36 ÷ 9 = 4$
$4 × 5 = 20$；$72 - 27 = 45$；$28 ÷ 8 = 3······4$
$37 + 28 = 65$；$2 × 3 = 6$；$48 ÷ 6 = 8$
$7 × 8 = 56$；$90 - 55 = 35$；$17 ÷ 2 = 8······1$
$77 - 55 = 22$；$8 × 9 = 72$；$38 ÷ 5 = 7······3$
$6 × 7 = 42$；$36 + 45 = 81$；$52 ÷ 7 = 7······3$

二、在一次学校运动会上，四名同学都参加了跳远比赛。下面是他们的比赛成绩，请帮他们排好名次。

二、小明 小刚
小强 小亮