《2025年口算训练三年级数学上册人教版双色升级版》

$205×7= $
$430×6= $
$308×3= $
$650×8= $
$306×4= $
$490×8= $
$307×5= $
$610×5= $
$708×9= $
$910×7= $
$203×8= $
$309×3= $
$920×8= $
$230×2= $
$880×7= $
$620×8= $
$740×8= $
$904×4= $
$603×5= $
$105×2= $

答案： 解析：本题主要考查了多位数乘一位数的口算能力。
答案：
$205×7=1435$
$430×6=2580$
$308×3=924$
$650×8=5200$
$306×4=1224$
$490×8=3920$
$307×5=1535$
$610×5=3050$
$708×9=6372$
$910×7=6370$
$203×8=1624$
$309×3=927$
$920×8=7360$
$230×2=460$
$880×7=6160$
$620×8=4960$
$740×8=5920$
$904×4=3616$
$603×5=3015$
$105×2=210$

$119×3\approx$
$711×3\approx$
$419×2\approx$
$299×4\approx$
$388×5\approx$
$598×4\approx$
$623×4\approx$
$689×3\approx$
$913×4\approx$
$201×3\approx$
$693×3\approx$
$298×6\approx$
$712×3\approx$
$291×6\approx$
$312×5\approx$
$201×9\approx$
$786×3\approx$
$307×6\approx$
$103×3\approx$
$999×3\approx$

答案： $119×3\approx 360$
$711×3\approx 2130$
$419×2\approx 840$
$299×4\approx 1200$
$388×5\approx 2000$
$598×4\approx 2400$
$623×4\approx 2480$
$689×3\approx 2070$
$913×4\approx 3640$
$201×3\approx 600$
$693×3\approx 2070$
$298×6\approx 1800$
$712×3\approx 2130$
$291×6\approx 1800$
$312×5\approx 1550$
$201×9\approx 1800$
$786×3\approx 2370$
$307×6\approx 1860$
$103×3\approx 300$
$999×3\approx 3000$

$27×(2)\approx 60$
$38×(2)\approx 80$
$79×(2)\approx 160$
$87×(2)\approx 180$
$17×(3或4)\approx 60$
$501×(5)\approx 2500$
$307×(6)\approx 1800$
$109×(6或7)\approx 700$
$305×(6)\approx 1800$
$204×(6)\approx 1200$
$(50)×5\approx 250$
$(80)×4\approx 320$
$(70)×8\approx 560$
$(40)×9\approx 360$
$(60)×7\approx 420$
$(700)×5\approx 3500$
$(900)×6\approx 5400$
$(500)×7\approx 3500$
$(900)×8\approx 7200$
$(300)×9\approx 2700$

答案： 解析：本题考查两位数乘一位数估算，将因数看成与之相近的整十、整百数再计算。
答案：
$27×(2)\approx 60$，
$38×(2)\approx 80$，
$79×(2)\approx 160$，
$87×(2)\approx 180$，
$17×(3或4)\approx 60$，
$501×(5)\approx 2500$，
$307×(6)\approx 1800$，
$109×(6或7)\approx 700$，
$305×(6)\approx 1800$，
$204×(6)\approx 1200$，
$(50)×5\approx 250$，
$(80)×4\approx 320$，
$(70)×8\approx 560$，
$(40)×9\approx 360$，
$(60)×7\approx 420$，
$(700)×5\approx 3500$，
$(900)×6\approx 5400$，
$(500)×7\approx 3500$，
$(900)×8\approx 7200$，
$(300)×9\approx 2700$。