1. Реши примеры: 65 * 3 = (60 + 5) * 3 = 60 * 3 + 5 * 3 = 180 + 15 = 195 93 * 4 = 78 * 2 = 31 * 3 =

Решение:

1. \( 93 \cdot 4 = \)

\( 90 \cdot 4 = 360 \)
\( 3 \cdot 4 = 12 \)
\( 360 + 12 = 372 \)

2. \( 78 \cdot 2 = \)

\( 70 \cdot 2 = 140 \)
\( 8 \cdot 2 = 16 \)
\( 140 + 16 = 156 \)

3. \( 31 \cdot 3 = \)

\( 30 \cdot 3 = 90 \)
\( 1 \cdot 3 = 3 \)
\( 90 + 3 = 93 \)

Ответ: 93 \(\cdot\) 4 = 372; 78 \(\cdot\) 2 = 156; 31 \(\cdot\) 3 = 93.