一、口算。
$660÷20=$ $800÷40=$ $65×20=$
$138+99=$ $185-78=$ $45÷15=$
$28×5=$ $360÷90=$ $800÷20=$
$700÷50=$ $120÷5=$ $40×12=$
$300÷2=$ $101×8=$ $76+29=$
$97-79=$ $500÷20=$ $99+33=$
$420÷30=$ $60×60=$ $137-28=$
$49+18=$ $720÷12=$ $86-38=$

33 20 1300 237 107 3 140 4 40 14 24 480 150 808 105 18 25 132 14 3600 109 67 60 48

$660÷20=33$
$800÷40=20$
$65×20=1300$
$138+99=237$
$185-78=107$
$45÷15=3$
$28×5=140$
$360÷90=4$
$800÷20=40$
$700÷50=14$
$120÷5=24$
$40×12=480$
$300÷2=150$
$101×8=808$
$76+29=105$
$97-79=18$
$500÷20=25$
$99+33=132$
$420÷30=14$
$60×60=3600$
$137-28=109$
$49+18=67$
$720÷12=60$
$86-38=48$

二、用竖式计算,带*的要验算。
$237÷38$ $459÷56$ *$343÷67$
$684÷36$ $338÷56$ *$270÷67$

6······9 8······11 5······8 19 6······2 4······2

343÷67=5······8


270÷67=4······2