If we divide 800/1000, we get .8 This means The price of $800 is only 80% of $1000. Furthermore, this also means that there was a decrease in price of 20%. The answer is C.
T because all variables are letters
You're correct, the answer is C.
Given any function of the form

, then the derivative of y with respect to x (

) is written as:

In which

is any constant, this is called the power rule for differentiation.
For this example we have

, first lets get rid of the quotient and write the expression in the form

:

Now we can directly apply the rule stated at the beginning (in which

):

Note that whenever we differentiate a function, we simply "ignore" the constants (we take them out of the derivative).
Answer:
A&B
Step-by-step explanation:
Answer:
Number of children, x= 400
Number of adults, y = 100
Step-by-step explanation:
Let the number of children be x
Let the number of adults be y
Given : Total number of people, x + y = 500 --------(1)
Total amount collected, 5x + 10y = 3000 ---------(2)
(1) => y = 500 - x
Substitute y in (2) : 5x + 10(500 - x) = 3000
5x + 5000 - 10x = 3000
-5x = 3000 - 5000
-5x = -2000
x = 400
Substitute x in (1) : 400 + y = 500
y = 500 - 400
y = 100