EXPLANATION
Price of shoes = $5.50
Markup= 40%
Let's call x to the unknown final price.
The markup percentage relationship is given by the following formula:
![\text{Markup =( }\frac{Selling\text{ Price}-\text{Cost Price}}{\text{Cost Price}})\cdot100](https://img.qammunity.org/2023/formulas/mathematics/college/uik8dsmgo7aot8tdhhyxfa2hn1p5n9zoqe.png)
Replacing terms:
![\text{40}=((x-5.5)/(5.5))\cdot100](https://img.qammunity.org/2023/formulas/mathematics/college/d7xek7huzzyabln335wnx130bkm9outpu6.png)
Multiplying both sides by 5.5:
![40\cdot5.5=(x-5.5)\cdot100](https://img.qammunity.org/2023/formulas/mathematics/college/5e1cag5u6kb6hfbx9idh7wcsr8cae2dpb1.png)
Dividing both sides by 100:
![(40\cdot5.5)/(100)=x-5.5](https://img.qammunity.org/2023/formulas/mathematics/college/gzq5zed33cupqe5xcsxdh5atkwel7vxsye.png)
Adding 5.5 to both sides:
![((40\cdot5.5)/(100))+5.5=x](https://img.qammunity.org/2023/formulas/mathematics/college/i78qfk183m93gek488tv3i6b64d6sk82bw.png)
Simplifyng the fraction:
![2.2+5.5=x](https://img.qammunity.org/2023/formulas/mathematics/college/swuppe4gmuep9ny3tasmxukwyhzklkup8t.png)
Adding numbers:
![\text{7}.7\text{ = x}](https://img.qammunity.org/2023/formulas/mathematics/college/zyuda3n8fxc18mdnw0xf2uu8ta5us49iym.png)
Switching sides:
![x=7.7](https://img.qammunity.org/2023/formulas/mathematics/college/a8jxwy0jgvvnq2ndcuhhu9wmdyyn4tjs2p.png)
Answer: The final price of the shoes in the deparment store is $7.7