Simplify the following expressions: 4. x * 2/9 * y * 3/20

Решение:

1. \[ x \cdot \frac{2}{9} \cdot y \cdot \frac{3}{20} = \left( x \cdot y \right) \cdot \left( \frac{2}{9} \cdot \frac{3}{20} \right) = xy \cdot \frac{2 \cdot 3}{9 \cdot 20} = xy \cdot \frac{6}{180} = xy \cdot \frac{1}{30} = \frac{xy}{30} \]

Ответ: \(\frac{xy}{30}\)