<h3>
Answer: 43 km per hour</h3>
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Work Shown:
total distance = 43+40+46 = 129 km
total time = 1+1+1 = 3 hours
average speed = (total distance)/(total time)
average speed = (129 km)/(3 hrs)
average speed = (129/3) (km/hr)
average speed = 43 km per hour
Take the derivative:
g’(x) = 12x^3 - 24x^2
Set equal to zero and solve:
0 = 12x^3 - 24x^2
0 = 12x^2 (x - 2)
x = 0 or x = 2
Plug back into original
g(0) = 3(0^4) - 8(0^3)
g(0) = 0 - 0
g(0) = 0
g(2) = 3(2^2) - 8(2^3)
g(2) = 3(4) - 8(8)
g(2) = 12 - 64
g(2) = -52
There is an absolute max at (0,0) or when x = 0
30% off 25: multiply 25 by .30 to find 30%: 7.5. Now subtract that from the sales price: 25-7.5=17.5
Do the same for store B: .40•30=12. 30-12=18.
So store A is better by $.50 :) hope this helps :)