《2025年聪明屋寒暑假作业系列丛书暑假作业四年级合订本》

1 孔雀王子会巧算。
$1658 + 85 + 472 + 115$ $478×6 + 6×522$ $125×99×8$
$50×137×2$ $4×25 + 6×25$ $101×45×2$

答案： 1658+85+472+115
=(1658+472)+(85+115)
=2130+200
=2330
478×6+6×522
=6×(478+522)
=6×1000
=6000
125×99×8
=125×8×99
=1000×99
=99000
50×137×2
=50×2×137
=100×137
=13700
4×25+6×25
=25×(4+6)
=25×10
=250
101×45×2
=101×(45×2)
=101×90
=9090

2 小熊在练习口算。
$478 - 396 = $82
$5500÷500 = $11
$18×4 = $72
$13×50 = $650
$3535÷35 = $101
$40×70 = $2800
$752 + 135 = $887
$452 + 48 + 500 = $1000
$50×400 = $20000
$490÷7 = $70
$320÷8 = $40
$372×10 = $3720

答案： 82 11 72 650 101 2800 887 1000 20000 70 40 3720