The first step is to find the difference between both values. This also means the change. Thus,
change = 478 - 250 = 228
We would express this change with respect to the original value and multiply by 100 since percentage is expressed in terms of 100. Thus, the percent change from 250 to 478 is
228/250 * 100
= 91.2
The percent change from 250 to 478 is 91.2%