Đặt tính rồi tính:

3 612 : 6 ………………….. ………………….. ………………….. …………………..

8 118 : 9 ………………….. ………………….. ………………….. …………………..

152 535 : 5 ………………….. ………………….. ………………….. …………………..

a) 4 × 78 × 5

= (4 × 5) × 78

= 20 × 78

= 1 560

b) 2 × 99 × 5

= (2 × 5) × 99

= 10 × 99

= 990

c) 6 × 31 × 5

= (6 × 5) × 31

= 30 × 31

= 930

d) 8 × 63 × 5

= (8 × 5) × 63

= 40 × 63

= 2 520

\[\begin{array}{l} \times \begin{array}{*{20}{c}}{15\,\,294}\\{\underline {\,\,\,\,\,\,\,\,\,\,\,\,\,\,3} }\end{array}\\\,\,\,45\,\,882\end{array}\]

\[\begin{array}{l} \times \begin{array}{*{20}{c}}{\,\,20\,\,613}\\{\underline {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,7} }\end{array}\\\,\,\,144\,\,291\end{array}\]

\[\begin{array}{l} \times \begin{array}{*{20}{c}}{372\,\,509}\\{\underline {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2} }\end{array}\\\,\,\,\,745\,\,018\end{array}\]