In order to get know which test is relative better, you have to use the formula to get the z score of psychology test and economics test.
Z=(raw score-sample mean)/standard deviation
Solution:
Psychology = (68 - 85) / 15 = -1.13
Economics = (59 - 65) / 10 = -0.6
Through this answer you can see that economics is closer to 0 which is the actual mean. This can be viewed through a normal distribution graph. The closer it is to 0, the relatively better it is because of it is more precise.
So economics is relatively better than psychology test.