Ok, MissWalker! Please try your best to understand this, it may get confusing.
I have solved this on a different website, and here is my solving in a picture. I hope I helped!!! :D
OK. Then let's solve for ' r '. That means you have to come up with an equation that says r = everything else.
Step #1:
Write the equation you're given: <span>S = L (1 - r)
Let's divide each side by ' L ': S/L = 1 - r
Subtract 1 from each side : S/L - 1 = -r
Multiply each side by -1 : <em> 1 - S/L = r</em>
and there you have it.
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The profit that is gained from the production and selling of the jeans is given to be calculated through the the equation,
P = 20x - 50
For 75 jeans, we just have to substitute 75 to the x's of the equation. This then becomes,
P = 20(75) - 50 = 1450
Thus, the company will make a profit of $1450 by production of 75 jeans.
The value of 28 tens is basically doing 28 times 10(in case you didn't know). 28 times 10 is 280. So the value of 280 tens is 280.