<PRE><B>Question 1039819</B>
average commute is 28 miles.


let x = the number of commuters.


the total distance traveled is therefore equal to 28 * x.


if you divide the number of commuters into 2 halves, then the total distance traveled by all commuters is 28 * 1/2 * x + 28 * 1/2 * x = 14 * x + 14 * x = 28 * x.


if half of the commuters drop their commute to 7 miles, then the total distance traveled by all commuters becomes 28 * 1/2 * x + 7 * 1/2 * x = 14 * x + 3.5 * x = 17.5 * x.


the total miles that x people commute becomes 17.5 * x.


the average number of miles that each person commutes becomes 17.5 * x / x = 17.5 miles.


the average commute drops from 28 miles to 17.5 miles.





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