Odpowiedź:
23.
a) 15 * 49 = 49 * 5 * 3 = 245 * 3 = 735
b) 51 * 12 = 51 * 4 * 3 = 204 * 3 = 612
c) 35 * 14 = 35 * 2 * 7 = 70 * 7 = 490
d) 15 * 61 = 61 * 5 * 3 = 305 * 3 = 915
24.
a) 63 * 11 = 63 * 10 + 63 * 1 = 630 + 63 = 693
b) 38 * 9 = 38 * 10 - 38 * 1 = 380 - 38 = 342
c) 54 * 21 = 54 * 20 + 54 * 1 = 1080 + 54 = 1134
d) 45 * 19 = 45 * 20 - 45 * 1 = 900 - 45 = 855
Szczegółowe wyjaśnienie:
