《2025年新课程能力培养四年级数学上册北师大版》

$35×17=$ $60×15=$
$85×24=$ $23×10=$

答案： $35 × 17$
$\begin{array}{r}35 \\× 17 \\\hline 245 \quad(35 × 7) \\+ 350 \quad (35 × 10)\\\hline 595 \end{array}$
$35 × 17 = 595$
$60 × 15$
$\begin{array}{r}60 \\× 15 \\\hline 300 \quad(60 × 5) \\+ 600 \quad(60 × 10) \\\hline 900 \end{array}$
$60 × 15 = 900$
$85 × 24$
$\begin{array}{r}85 \\× 24 \\\hline 340 \quad(85 × 4) \\+ 1700 \quad(85 × 20) \\\hline 2040 \end{array}$
$85 × 24 = 2040$
$23 × 10$
$\begin{array}{r}23 \\× 10 \\\hline 230 \end{array}$
$23 × 10 = 230$