US System for counting fortune is quite different from ours.
They Count it as
1000= 1 Thousand
Thousand x 1000 =1 Million
1 Million x 1000 =1 Billion
1 Billion x 1000 =1 Trillion
And now back to your question
1 billion = 100 crore
$ 1 billion = $ X 100 Crore
Whenever you want to calculate Rupees equivalent to 1 Billion USD just multiply 100 crore by the current exchange rate. It varies every day.
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