9•(4•25) 15•(4•9) 11•(10•3) 10•(29•2)

1 ) 9 • ( 4 • 25 ) = 9 * ( 4 * 20 + 4 * 5 ) = 9 * ( 80 + 4 * 5 ) = 9 * ( 80 + 20 ) = 9 * 100 = 9002 ) 15 • ( 4 • 9 ) = 15 * 36 = 15 * 30 + 15 * 6 = 15 * 10 + 15 * 10 + 15 * 10 + 10 * 6 + 5 * 6 = 150 + 150 + 150 + 60 + 30 = 300 + 150 + 60 + 30 = 450 + 60 + 30 = 450 + 50 + 10 + 30 = 500 + 10 + 30 = 500 + 40 = 540 3 ) 11 • ( 10 • 3 ) = 11 * 30 = 11 * 10 + 11 * 10 + 11 * 10 = 110 + 110 + 110 = 100 + 10 + 100 + 10 + 100 + 10 = 300 + 30 = 330 4 ) 10 • ( 29 • 2 ) = 10 * ( 20 * 2 + 9 * 2 ) = 10 * ( 20 + 18 ) = 10 * 38 = 380