The Jaspers collect nickels, dimes, and quarters in a jar. When they count the change in the jar, there are twice as many nickels as there are quarters. If there is $15.30 in dimes and $74.80 in all, how many quarters are there. Please include an equation and steps.

N = 2Q

74.80 - 15.30 = 59.50

.05N + .25Q = .05(2Q) + .25Q = 59.50

Solve for Q.