Answer:
360 mi/h
Step-by-step explanation:
The speed for the outbound trip was ...
speed = distance/time = (715 mi)/(2 1/6 h) = 330 mi/h
The inbound speed was ...
(715 mi)/(1 5/6 h) = 390 mi/h
The airspeed of the plane is the average of these two ground speeds, so is ...
(330 +390)/2 = 360 . . . . mi/h
The number that represents 8/9 to the nearest percent is .89
F(x) = -2.5x + 135...where x is the number of weeks, and f(x) = total weight
