



 
Hi Johanna, If I understand correctly you have added 35% to your cost and arrived at $\$70.$ Thus if your cost is $C$ dollars then \[C + 0.35 \times C = \$70.\] That is \[1.35 C = \$70.\] Dividing both sides by 1.35 gives \[C = \frac{\$70}{1.35}.\] Penny  


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