It is reasonable. Since 255,113 is closer to 300,000 than 200,000 on the number line, you can round the number to 300,000.
Step 1: Find the slope:

Step 2: Set up your equation
using one of the points.
Using (5,6) we have
.
Using (6,10) we have 
Both of those equations would be correct.
Hi bubonic bunkhouse boohoo ignominious globulin honing
Lets use 1 to solve this problem because it is easiest to show.
Multiply 1 by 1.3 for a 30% increase (1*1.3=1.3).
Then multiply 1.3 by .7 for a 30% decrease. (1.3*.7=.91)
Therefore the page had a 9% reduction from its original size or is 91% of its original size.