Вычесли удобным
25•3•8•4=?
35•6•5•3=?
15•7•2•10=?
15•12•2•5=?

Пошаговое объяснение:

1) 40*7*3=280*3=840

2)100*3*8=300*8=2400

3)210*5*3=1050*3=3150

4)150*7*2=1050*2=2100

5)15*12*10=150*12=1800

8•7•5•3 = (8•5)•(7•3) = 40•21 = 840

25•3•8•4 = (25•4)•(3•8) = 100•24 = 2400

35•6•5•3 = (35•6)•(5•3) = 210•15 =

= (200 + 10)•15 =

= 3000 + 150 = 3150

15•7•2•10 = (15•(2•10))•7 = 300•7 = 2100

15•12•2•5 = 15•(2•5)•(10 + 2) =

= 15•10•(10 + 2) =

= 150•(10 + 2) =

= 1500 + 300 = 1800