Ashley has 36 coins totaling $4.20 in quarters and dimes. How many of each coin does she have?
+36915 d = dimes value = 10d
q = quarters = 36-d value = 25 (36-d) summed , these two = 420
10 d + 25(36-d) = 420 solve for d = the number of dimes ...then quarters = 36 - d
