Question 1036252
Let t = # of 2 cent stamps, and s = # six cent stamps.

==> s = t-5, and  0.02t + 0.06s = 0.74.

==> 0.02t + 0.06(t-5) = 0.74

<==> 0.02t + 0.06t - 0.3 = 0.74

==> 0.08t = 1.04

==> t = 13, the number of two-cent stamps, and 
s = t-5 = 8, the number of six-cent stamps.