



 
Hi Jimi. Ten percent of the sales is the profit, which becomes her earnings. So we can solve this with algebra.
We want to find the value of S, so we need to make the left side of the equation just S (this is called isolating S). That means we have to get the 10% out of the left side of the equation. To do that, we will divide by 10% on both sides of the equation. Then the 10% cancels out on the left side:
therefore
Now remember that percent means per hundred, so 10% means 10 / 100, which is 0.10. So we can write it like this:
Can you finish the question now?  


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