Question 133975
You don't say whether $1.00 and/or $0.50 coins are available.  Let's exclude the $1.00 coin because that is trivial.  So you have four different coins available, half-dollar, quarter, dime, and at most one nickel.


You could use two half dollars


You could use one half dollar and two quarters


One half dollar, one quarter, two dimes and one nickel


One half dollar, no quarters, and five dimes


(You can't have one half dollar, no quarters, four dimes and two nickels because that violates the 'one nickel' rule)


No half dollars, three quarters, two dimes, one nickel


No half dollars, two quarters, five dimes


No half dollars, one quarter, seven dimes, one nickel


Ten dimes


All together, 8 ways.  If you don't have half dollar coins, then only count the ways that don't use half dollars, total 4.