Answer: 5.46 billion
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Step-by-step explanation:
If you mean the world's population, then there are roughly 7.8 billion people on earth.
70% of that is 0.70*7.8 = 5.46 billion
The number 5.46 billion can be written as 5,460,000,000
This number is read out as "5 billion, 460 million"