13*3 = 10*3 + 3*3 = 30 + 9 = 39
12*4 = 10*4 + 2*4 = 40 + 8 = 48
(5 + 2) * 60 = 7 * 6 * 10 = 42 * 10 = 420
(14 + 6) * 2 = 20 * 2 = 40
13 * 30 = 13 * 3 * 10 = 39 *10 = 390
14 * 20 = 14 * 2 * 10 = 28 * 10= 280
(40 + 20)* 2 = 60 * 2 = 120
(22 + 8) * 3= 30*3=90
12*40=12*4*10=48*10=480
21*40=21*4*10=84*10=840
(20+4)*2= 40 + 8 = 48
(31 + 19) * 20 = 50 *2*10=100*10=1000
130 * 2= 13*2*10=26*10=260
410*2=41*2*10=82*10=820
Пошаговое объяснение:
