



 
Hi Linda, Suppose you knew the number, for example suppose the number is 7. The instructions then say
If the number is 9 then 3 times the number is $3 \times 9$ and "four less than three times the number" is $3 \times 9  4.$ (If 9 were the correct then this would be 20 which it is not.) In algebra we pretend we know the number, give it a name and repeat the steps above. I am gong to name the unknown number $n.$ In that case 3 times the number is $3 \times n$ and 4 less than 3 times the number is $3 \times n  4.$ The problem states that the result of this calculation is 20 and hence \[3 \times n  4 = 20.\] Solve for $n.$ Once you have $n$ you can verify your answer. Calculate $3 \times n  4.$ Did you get 20? Penny 



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