## Elementary Algebra

We are told: $d + q + n = 20$ And $.1d + .25q + .05n = 3.4$ And $d + n = q$ Substituting q for d + n in equation one, we obtain: $2q = 20 \\ q = 10$ Thus, we are left with: $.1d + .05n = .9$ And $d + n = 10$ Using d = 10 - n, we find: $.1(10 - n) + .05n = .9 \\ -.05n = -.1 \\ n = 2$ This means that the number of dimes is: $d = 10 -2 = 8$