2,000 IBs (pounds) are in a ton.
Answer:

Step-by-step explanation:
We are given the following in the question:
Quantity, q
Selling price in dollars per yard, p

Total revenue earned =

f(20)=13000
This means that 13000 yards of fabric is sold when the selling price is 20 dollars per yard.
f′(20)=−550
This means that increasing the selling price by 1 dollar per yards there is a decrease in fabric sales by 550.
We have to find R'(20)
Differentiating the above expression, we have,

Putting the values, we get,

There is no fixed equation when I arrived at these numbers.
I just did trial and error. I came up with 25 and -8 as the numbers.
200 ÷ 25 = 8 ⇒ the sum of 17 depends on the signs of each numbers.
-8 x 25 = -200
-8 + 25 = 17
Answer:
1/2
Step-by-step explanation:
3/5 - 1/10
6/10 - 1/10 = 5/10 = 1/2
-2 is the slope of the line