The ratio between the Shanghai and Shenzhen 300 Index and the 50 Index is not even. What is the proportion of these 50 stocks? Yes: the proportion of stocks is the proportion of their market value (300 market value or 50 market value) to the total market value.

The ratio you mentioned is called weight in socio-economic statistics. This index is actually a weighted average of stock prices, not an arithmetic average, and its essence is the average price.

Funds can be bought in banks and securities companies, or in fund companies. The same fund purchased by different banks, securities companies and fund companies has different subscription rates, but the fund is still the same.

Fund companies have index funds, such as E Fund and harvest fund. What is the difference?

This question is too big to answer.