Question

Tinh Nhanh : 7,38 *0,5 *20     2,5*4,69*40     9,18*80*1,25

Answer 1

0,5*20=10 10*7,38=73,8

2,5*40=100 100*4,69=469

1,25*80=100 100*9,18=918

Answer 2

7,38.0,5.20

=7,38.10

=73,8

Answer 3

      \(7,38\cdot0,5\cdot20\)

\(=7,38\cdot\left(0,5\cdot20\right)\)

\(=7,38\cdot10\)

\(=73,8\)

        \(2,5\cdot4,69\cdot40\)

\(=\left(2,5\cdot40\right)\cdot4,69\)

\(=100\cdot4,69\)

\(=469\)

      \(9,18\cdot80\cdot1,25\)

\(=9,18\cdot\left(80\cdot1,25\right)\)

\(=9,18\cdot100\)

\(=918\)