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 =




Isolate variable terms.


Multiply both sides by 2.

Divide both sides by 5.


Therefore, the required number is -60.