<PRE><B>Question 1200411</B>
&lt;br&gt;
The problem tells you what operations were performed on the starting number, and it tells you what number you ended up with.&lt;br&gt;
One way to find what number you started with is to work backwards: take the number you started with and perform the OPPOSITE operations in the OPPOSITE order.&lt;br&gt;
The operations you performed on the number you started with were (1) subtract 8 and (2) multiply by 3.&lt;br&gt;
To get back to the original number from the number you ended up with, you need to (1) divide by 3 and (2) add 8.&lt;br&gt;
21/3 = 7; 7+8 = 15&lt;br&gt;
ANSWER: 15&lt;br&gt;
Note that in solving the problem using the standard algebraic method those are exactly the steps you need to do -- divide by 3 and then add 8:&lt;br&gt;
3(x-8) = 21  [given]
x-8 = 21/3 = 7  [divide by 3]
x = 7+8 = 15  [add 8]&lt;br&gt;
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