Q136 of 196 Page 249

At the end of the 20th century, the world population was approximately 6.1 × 109 people. Express this population in usual form. How would you say this number in words?

The world population at the end of 20th century = 6.1 × 109 people


Usual form of 6.1 × 109 = 6.1 × 1, 000, 000, 000


= 6, 100, 000, 000


6, 100, 000, 000 can be read as six billion one hundred million.


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