Question 360911
This is a relatively simple solution that you can use with a lot of percentages:

68÷80

That's it. 
68÷80=.85
.85x100=85%

You can apply the same technique to other percentage problems as well:

94/143 on a test is 94÷143. 94÷143=.66, .66x100=66%. 

Good luck!

~IW4D