



 
Hi Mark, We have two responses for you I am not surprised that you are baffled by this question. It is an extremely confusing way to ask a very natural question. How about this?
To me this is a much more natural way to ask the question. I would answer something like this.
If he wanted one of width 12 inches then, since $12 = 3 \times 4$ he would need a length of $5 \times 4 = 20$ inches. Similarly if he wanted one of width 1 inch, then since 1 is onethird of 3 he would need a length of onethird of 5 inches or $\frac13 \times 5 = \frac13 (5) = \frac53$ inches. This is how the textbook author comes up with the algebraic expression "1/3(5w)." Here w stands for the width the designer wants and then the length is 1/3(5w), or I would prefer to express it $\frac53 w.$ Penny
The question is not phrased as a question! This is a bad habit of some math text writers. The implied question is: if the width w = 6 inches, find 1/3(5w). Does this help? Good Hunting!  


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