Answer:
65 miles
Step-by-step explanation:
The straight line distance between two points can be considered to be the hypotenuse of a right triangle. In this case, the legs of the triangle are the distance east and the distance north. The Pythagorean theorem describes the relation between the legs (a, b) and the hypotenuse (c).
c² = a² +b²
c² = 60² +25² = 3600 +625 = 4225
c = √4225 = 65
The two airports are 65 miles apart.
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Additional comment
You may recognize that the greatest common factor of 25 and 60 is 5, which means these numbers have the ratio 5 : 12. You may also recognize these as being the two smaller numbers in the Pythagorean triple {5, 12, 13}. That is, you expect the airports to be 5×13 = 65 miles apart.
