Question 1181517
In a collection of coins there are twice as many nickels as dimes and 7 less quarters than dimes. 

If dimes are x then nickels are 2x

quarters are x-7

Total is $16.25 = 1625 cents

10x + 5(2x) +25(x-7)=1625

20x + 25x - 175 = 1625

45x = 1800
x = 40 
Dimes - 40
Nickels = 2x = 80
quarters x-7 = 33