《2025年暑假作业安徽少年儿童出版社四年级数学苏教版》

5 下面各题,怎样简便就怎样算。
$162+49+161$ $83× 24× 5$
$4× 75× 25$ $496-172-28$
$125× 32$ $593+86-193$
$751+198$ $151+43+55+57+49$
$24× 125$ $35× 7× 2$
$25× 16$ $4× (25× 9)$
$25× 27× 4$ $125× 7× 8$

答案： 162+49+161
=162+(49+161)
=162+210
=372
83×24×5
=83×(24×5)
=83×120
=9960
4×75×25
=(4×25)×75
=100×75
=7500
496-172-28
=496-(172+28)
=496-200
=296
125×32
=125×8×4
=1000×4
=4000
593+86-193
=593-193+86
=400+86
=486
751+198
=751+200-2
=951-2
=949
151+43+55+57+49
=(151+49)+(43+57)+55
=200+100+55
=355
24×125
=3×8×125
=3×(8×125)
=3×1000
=3000
35×7×2
=35×2×7
=70×7
=490
25×16
=25×4×4
=100×4
=400
4×(25×9)
=4×25×9
=100×9
=900
25×27×4
=25×4×27
=100×27
=2700
125×7×8
=125×8×7
=1000×7
=7000

1 下图中每个书架有4层,每层放了23本书,5个书架一共放了多少本书？

答案： 解：4×23×5
=92×5
=460（本）
答：5个书架一共放了460本书。