Question 1204741
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n = number of months
2n = number of pounds lost over those n months
220 = starting weight
220 - 2n = final weight
220 - 2n < 200
-2n < 200 - 220
-2n < -20
n > -20/(-2) .... inequality sign flip
n > 10


Another way to solve
220 - 2n < 200
220 < 200+2n
2n+200 > 220
2n > 220-200
2n > 20
n > 20/2 .... no sign flip this time
n > 10
The inequality sign only flips if dividing both sides by a negative number.



Answer: Evan needs to be on the diet for more than 10 months to reach his goal weight.
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