Lant Pritchett said this quote

“ Perhaps more surprising, even the rich in developing countries also lag. For example, in Indonesia, the richest quintile has scores around 450--less than the 500 for the poorest quintile in Korea or the same as the poorest quintile in UK. So in poor countries, the richest are still getting a mediocre education, and the poor cannot be said to be getting any education at all. ”