The average speed of one airplane is 200 mph faster than that of an automobile. if the automobile starts at 3 a. m. and the airplane starts from the same place at 11 a. m., they will have traveled the same number of miles by 1: 00 p. m. if r represents the rate of the automobile, how many miles does the plane travel?
a. 200r
b. 2(200 + r)
c. 10r

Step-by-step explanation:

Let the speed of the car be "X". From 3 am until 1 pm (10 hours), the car will travel 10*X miles. 

The speed of the airplane is (X +200). From 11 am until 1 pm (2 hours), the plane will travel 2*(X+200). 

The distance travelled is the same, so: 

10*X = 2*(x+200)= 2x+400 

Subtract 2*X from both sides: 

8*X = 400

X = 400/8 = 50 mph.

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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