A number decreased from $80$ to $50$. By what percent of its original value has this number decreased? Write the answer in the form of the nearest integer greater than the answer.

When the number decreases, it decreases by $(80-50)=30$ and the original number was $80$. 

Hence the percentage of decrease $=\frac{30}{80}\times 100$

                                                            $=37.5\%\approx 38\%$