Final answer:
The airplane was originally at 20000 feet in altitude. After dropping 2500 feet, its new altitude is 17500 feet.
Step-by-step explanation:
The concept being addressed here is basic subtraction and understanding the concept of altitude.
Given, the initial altitude of the airplane is 20000 feet. The airplane then drops 2500 feet in altitude.
Therefore, to find the new altitude, we simply subtract the altitude lost from the initial altitude:
Initial Altitude - Altitude Loss = New Altitude
20000 feet - 2500 feet = 17500 feet
So, the airplane's new altitude is 17500 feet.
Learn more about Subtraction
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