Answer:San Diego plane traveling at 250
San Fran plane traveling at 300
Explanation:
(1/2)(x-50) + (1/2)x = 275
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(x-50) + x = 550
2x = 600
x = 300 mph (speed of the north-bound plane )
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x - 50 = 250 mph (speed of the soutn-bound plane)
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