Question

Обчисліть зручним способом: 1) 31 * 61 + 31 * 39 3) 48 * 62 - 28 * 62 2) 115 * 17 - 15 * 17 4) 45 * 13 + 45 * 17.​

Answer 1

Ответ:

Смотри решение на фото ниже

Answer 2

Ответ:

Пошаговое объяснение:

Обчисліть зручним способом:

1) 31 * 61 + 31 * 39=31(61+39)=31*100=3100;

3) 48 * 62 - 28 * 62 = 62(48-28)=62*20=1240;

2) 115 * 17 - 15 * 17 = 17(115-15)=17*100=1700;

4) 45 * 13 + 45 * 17. = 45(13+17)=45*30​=1350.

Answer 3

1) 31 * 61 = 1891 31 * 39 = 1209 Simplifying, we can add the two products together: 1891 + 1209 = 3100

2) 48 * 62 = 2976 28 * 62 = 1736 One way to calculate this is: 2976 - 1736 = 1240

3) 115 * 17 = 1955 15 * 17 = 255 Subtracting the two products: 1955 - 255 = 1700

4) 45 * 13 = 585 45 * 17 = 765 Adding the two products: 585 + 765 = 1350

Using these methods, we can calculate the respective equations: 1) 31 * 61 + 31 * 39 = 3100 2) 48 * 62 - 28 * 62 = 1240 3) 115 * 17 - 15 * 17 = 1700 4) 45 * 13 + 45 * 17 = 1350