Answer: The size of computer display after 20 % increase and then 20 % decrease= 96 % of the original size.
Step-by-step explanation:
Let the original size of computer be 100x , then if it increases by 20 %
then the new size of the computer=100x +20% of 100x

The size of computer after 20% increase= 120x
If size of computer is decreased by 20 % then
The new size of computer= 120x - 20% of 120 x

On comparing it to the original size , we get

Thus, the size of computer display after 20 % increase and then 20 % decrease= 96 % of the original size.