Top 10% of Bengalis have 35% of the income, in a country with a purchasing-power parity (PPP) income per capita of $1909. So my guess would be top decile makes about $6-7k/year. This is in a country with zero public services (while someone living on $10k/year in the U.S. has access to public education,* public housing, food stamps, Medicaid, etc). India is substantially better, but at around double the PPP income of Bangladesh, that puts top 10% of Indians probably right around the bottom 10% of Americans.

*) American school spend on average $10k/year per student.