Answer:
-60.
Explanation:
Let the unknown number be x.
Number is increased by 26 = x+26
Then result is tripled = 3(x+26)
Then the result is increased by 72 = 3(x+26)+72
Final result is
of the number =
![(1)/(2)x](https://img.qammunity.org/2021/formulas/mathematics/college/4t1dkiu1dkp7c3wlt6rur5ertlrhp5kq10.png)
![3(x+26)+72=(x)/(2)](https://img.qammunity.org/2021/formulas/mathematics/college/2dnugg7jq3nzrz65vzsdjlqxgfjidb0fs6.png)
![3x+78+72=(x)/(2)](https://img.qammunity.org/2021/formulas/mathematics/college/a6m8bszwsgsmoleb93p4sriwq416zwdkip.png)
![3x+150=(x)/(2)](https://img.qammunity.org/2021/formulas/mathematics/college/nv6qf0lndctbd65obp5x1v4gog5w50srez.png)
Isolate variable terms.
![3x-(x)/(2)=-150](https://img.qammunity.org/2021/formulas/mathematics/college/l8kdq21fqv0q94dzz8aydeodrs8prcdmmh.png)
![(6x-x)/(2)=-150](https://img.qammunity.org/2021/formulas/mathematics/college/6vk88dzu09jy04etz92w94ewg678hiya8n.png)
Multiply both sides by 2.
![5x=-300](https://img.qammunity.org/2021/formulas/mathematics/college/3zhmisgk4j1qciyz56nzwfkpyq9v0syzxf.png)
Divide both sides by 5.
![x=-(300)/(5)](https://img.qammunity.org/2021/formulas/mathematics/college/eul6li6x37oeexbi9cinwc62mj4nzfdrhn.png)
![x=-60](https://img.qammunity.org/2021/formulas/mathematics/college/xd8n3sfc65q1zk0oxnnryz5ywx3vafcspv.png)
Therefore, the required number is -60.