Answer:
there was a 16% increase since 2010 to 2012
Step-by-step explanation:
lets say the train had 100 people on it in 2010 and in 2011 it had an 8% increase which then brings you to 8 plus 100 and you get 108.
Now in 2012 there was an increase 8%, so you will add 8 to your previous answer 108 and receive 116. So now there was 16 more passengers in 2012 than in 2010. Transfer the 16 passengers into 16% and you now have your answer.
If x and y vary inversely, then xy = const.
x = 10, y = 8

-1.5 + 7.5
factor out -1.5, divide 7.5 by 1.5 to factor it out of it as well (7.5 divided by -1.5) and make sure you get NEGATIVE 5.
-1.5(1 x -5)