59} Research shows that 10% of th graders in [(6 schools have tried cigarettes and 60% of 7th graders in 8-9 or 7-9 middle schools have tried...

I am having a bit trouble with understanding the increase percentage between two percentages - Here is the problem hopefully you can help me understand this fully:

59} Research shows that 10% of fith graders in [(—6 schools have tried cigarettes and 60% of 7th graders in 8-9 or7-9 middle schools have tried cigarettes. The percent increase, to the nearest percent. is