To do this, we must set up ratios:
Option One:
The first options costs only
$0.0092/gram (a fraction of a penny)!
Option Two:

The second option costs only
$0.0085/gram (cheaper than option one)!
Option Three: This requires a little more work. First, we have to convert the grams into kilograms. For every 1 kg, there is 1,000 g. Therefore,
1,000g costs $5.65. Next, we set up the ratio as usual:

The third option costs
$0.00565/gram.
Therefore,
option three is the cheapest! Hope this helps!

Differentiate both sides wrt
:

By the chain rule, we get


Solve for
:


Answer:
$25.86
Original price. 30.00
Markdown percent 16%
Markdown 4.14
Step-by-step explanation:
Unfortunately, you inadvertently cut off the instructions for this problem when you photographed it. Could you try again, making certain to include the instructions?
Let me guess: perhaps the instructions are 1) determine the slope of the line passing through the given points, or 2) write the equation of the line passing through the given points.