解:①、(24×
![](http://thumb.1010pic.com/pic5/latex/597.png)
+7)÷
![](http://thumb.1010pic.com/pic5/latex/729.png)
,
=(9+7)÷
![](http://thumb.1010pic.com/pic5/latex/729.png)
,
=16×
![](http://thumb.1010pic.com/pic5/latex/4491.png)
,
=18.
答:这个数是18.
②、(
![](http://thumb.1010pic.com/pic5/latex/155.png)
-4×
![](http://thumb.1010pic.com/pic5/latex/112.png)
)÷
![](http://thumb.1010pic.com/pic5/latex/168.png)
,
=(
![](http://thumb.1010pic.com/pic5/latex/155.png)
-
![](http://thumb.1010pic.com/pic5/latex/13.png)
)×
![](http://thumb.1010pic.com/pic5/latex/33.png)
,
=
![](http://thumb.1010pic.com/pic5/latex/8.png)
×
![](http://thumb.1010pic.com/pic5/latex/33.png)
,
=
![](http://thumb.1010pic.com/pic5/latex/13.png)
.
答:商是
![](http://thumb.1010pic.com/pic5/latex/13.png)
.
③、除数是:(454-26-12-26)÷(12+1),
=390÷13,
=30;
被除数是:12×30+26,
=360+26,
=386.
答:被除数是386,除数是30.
分析:①先计算出24的
![](http://thumb.1010pic.com/pic5/latex/597.png)
,再加上7,最后再除以
![](http://thumb.1010pic.com/pic5/latex/729.png)
即可;
②先计算
![](http://thumb.1010pic.com/pic5/latex/155.png)
减去4的
![](http://thumb.1010pic.com/pic5/latex/112.png)
差,再除以
![](http://thumb.1010pic.com/pic5/latex/168.png)
即可;
③根据被除数=商×除数+余数可知,被除数减去余数,就是除数的12倍,即被除数-26=除数×12;被除数、除数、商、余数的和等于454,454减去余数和商,就是被除数与除数的和,即被除数+除数=454-26-12,那么,(被除数-26)+除数=454-26-12-26,根据和倍关系,较小数=和÷(倍数+1),进一步计算即可.
点评:①和②根据文字叙述,找清数量关系和运算顺序,比较容易列式计算;③要根据有余数的除法中被除数=商×除数+余数这个关系,再根据题意,找出被除数与除数的和倍关系,进一步解答即可.