You can put this solution on YOUR website! Given to solve for r:
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The form is a quantity on the left side and a fraction on the right side. A quick way to think about problems of this form is that you can just swap the quantity of the left side with the denominator on the right side and solve. When you do that the problem becomes:
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And doing the division on the right side (divide 7 into 420) results in:
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To show that this "short way" of doing the problem is correct, let's work it out a little longer way. To get rid of the denominator on the right side, multiply both sides by r to get:
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Cancel the r in the denominator with the r multiplier:
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and you are left with:
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Solve by dividing both sides of the equation by 7:
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Same answer as before, but just a few more steps in the thought process.
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Hope this helps you to understand the problem.
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