The required value for the sum is 9580.

<h3>What is simplification?</h3>
Simplification in mathematics to solve the given condition on its operators.

= 
= 9580
The required solution is given as 9580.
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It neve mentions how much of his farm he uses, but assuming he uses all of it
area=base times height
given
base=4.2
height=3
area=4.2 times 3
area=12.6 square kilometers
answer is 12.6 km²
X - y = 2400/6 = 400 where x = speed of plane and y = speed of wind.
x + y = 2400/5 = 480 - flying with the wind
adding the 2 equations
2x = 880
x = 440
Speed of the plane with no wind = 440 mph
No Jeff is wrong, -2 has a higher value than -3.