Answer
$250,000,000 = 2.5 \times 10^8$
Work Step by Step
Move the decimal point until the number is between 1 and 10.
$250,000,000. $ -> $2.5$
The decimal point is moved 8 places and the original number is 10 or greater, so the count is positive 8.
$250,000,000 = 2.5 \times 10^8$