To answer this item, we take the differential of the equation and equate to zero.
C(x) = 0.8x² - 256x + 25939
Differentiation,
dC(x) = 1.6x - 256
dC(x) = 1.6x - 256 = 0
The value of x from the derived equation above is 160.
Thus, the number of machine to be made in order to minimize the cost should be 160.
Is it 4 times x or 4 to the power of x, if the first one then, 8x-24x. if the second then 8^-6x
DC :AB=3:2 can be written as
DC/AB=3/2
Then you can get the answers easily
You would need to leave the dentist at 2:40.
I prefer to use compatible numbers because by using this method it is easier to make a sum mentally. This is true because compatible numbers are close in value to the actual numbers. For a better understanding, let's take an example:
Suppose you have two numbers, namely 640 and 40. These two numbers are compatible for division because:
64 ÷ 4 = 16
So, we have used mental arithmetic to solve a more complex problem.
