1040 at .309 and 2112 at .534
(.309 X A) + (.534 X b) = 1449.168 (1449.168 was total postage used)
.534 - .309 = .225
.534 X 3152 = 1683.168 (3152 is total envelopes posted)
1683.168 - 1449.168 = 234
234 / .225 = 1040
A = 1040
3152 - 1040 = 2112
B = 2112
