Inequalities in word problems

bravof

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Hi,

I am studying for the SAT and came across this problem but the explanation Khan Academy gives does not really help at all. Please help, thank you!

An ice cream truck owner has determined that his maximum revenue occurs when he sells 1,250 cones per month. For every cone above or below 1,250 that he sells, his revenue decreases by $0.15. Which of the following equations can be used to find the possible numbers of cones, c for which the revenue decreases $250 from the maximum?
 
Hi,

I am studying for the SAT and came across this problem but the explanation Khan Academy gives does not really help at all. Please help, thank you!

An ice cream truck owner has determined that his maximum revenue occurs when he sells 1,250 cones per month. For every cone above or below 1,250 that he sells, his revenue decreases by $0.15. Which of the following equations can be used to find the possible numbers of cones, c for which the revenue decreases $250 from the maximum?
Can you write the revenue function?

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this problem.
 
Here is the problem with the answer and explanation that khan Academy gave. I am having trouble understanding how the numbers in the equation relate to problem.
 

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If you sell exactly 1250 cones you make a certain about of money, call it $m

Now for each cone you sell above or below 1250 you lose $.15per cone

So if you sell say 1275 cones, which is 25 more than 1250, then you will make 25*$.15 less than $m.
If you sell 1000 cones, which is 250 less than 1250, then you will make 250*$.15 less than $m

So how do you express the difference between the number of cones which you sell, c, and 1250. The answer is |c-1250|.
Show much less do you make less than $m?
Answer is $.15|c-1250|. Now you want this amount to be $250. So $.15|c-1250|=$250
 
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