How you write 1.6 billion?

Answer 1

1,600,000,000
Reason:

Thousand has three zeros. (ex: 1,000.)

Million has six zeros. (ex: 1,000,000.)

Billion has nine zeros. (ex: 1,000,000,000.)

A decimal separates the 1 from the 6. The 1 is in the billions spot. Since the 6 is to the immediate right of the decimal point, it is in the place of the hundreds-unit in the millions section.

So the answer is 1,600,000,000 which is pronouced: "One billion Six hundred million".