Answer: 28 nickels and 13 quarters
Explanation:
Let the number of nickels represented by x and the number of quarters represented by y.
Then according to the question, we have the following equations :
Divide 0.05 on both sides of equation (2), we get

Subtract equation (1) from equation (3) , we get

From (1), x=28
Therefore, there are 28 nickels and 13 quarters.