JAMIL always throws loose change into a pencil holder on his desk and takes it out every two weeks. this time it is all nickels and dimes . there are 9 times as many dimes as nickels, and the value of the dimes is $6.80 more than the value of the nickels, How many nickels and dimes dose jamil have

dime = 10 cents, nickel = 5 cents

Let there be x nickels, so there are 9x dimes. 

value of nickel = 5x value of dimes = 90x

85x = 680

x = 8