Answer:
7,000,000,000
Explanation:
Note the Billions place value. 7 is in the billions place value. To find out if you round up or down, look at the place value directly to the right of the one you are trying to find, in this case, being the hundred million place value. The value inside the hundred million place value is a 1.
Note that the number has to be 5 or greater to round up, or else you round down. Because 1 < 5, you round down.
7,125,000,000 rounded to the nearest billion is 7,000,000,000.
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