Answer:
x - 231 ≤ 459
Step-by-step explanation:
Given:
Elevation ranges below sea level = 228 ft
Elevation ranges above sea level = 690 ft
Elevation = x
Computation:
Ideal range = [690-228] / 2 = 231
Tolerance range = [690+228] / 2 = 459
So,
x - 231 ≤ 459
14.9. this is because 8 is in the tenth place, and the next number is five. for numbers greater than 4, you round up, for four or less, you stay the same.