一、口算。
$82 - 54 =$         $6×5 =$         $34÷6 =$
$8×4 =$         $60 - 22 =$         $33÷7 =$
$37 + 26 =$         $7×7 =$         $72÷8 =$
$2×6 =$         $55 - 37 =$         $18÷4 =$
$43 + 48 =$         $3×8 =$         $27÷5 =$
$3×7 =$         $76 - 49 =$         $12÷3 =$
$7×6 =$         $42 + 27 =$         $55÷6 =$
$70 - 54 =$         $6×9 =$         $51÷9 =$
$5×9 =$         $37 + 37 =$         $17÷7 =$
$52 - 24 =$         $8×5 =$         $25÷5 =$

$82 - 54 = 28$；$6×5 = 30$；$34÷6 = 5······4$
$8×4 = 32$；$60 - 22 = 38$；$33÷7 = 4······5$
$37 + 26 = 63$；$7×7 = 49$；$72÷8 = 9$
$2×6 = 12$；$55 - 37 = 18$；$18÷4 = 4······2$
$43 + 48 = 91$；$3×8 = 24$；$27÷5 = 5······2$
$3×7 = 21$；$76 - 49 = 27$；$12÷3 = 4$
$7×6 = 42$；$42 + 27 = 69$；$55÷6 = 9······1$
$70 - 54 = 16$；$6×9 = 54$；$51÷9 = 5······6$
$5×9 = 45$；$37 + 37 = 74$；$17÷7 = 2······3$
$52 - 24 = 28$；$8×5 = 40$；$25÷5 = 5$

二、根据小朋友们的对话找到他们跑步所用的时间，并连一连。

1分12秒 1分6秒 58秒