Solution:
Let stamps be s and postcards be p
Given that,
The number of stamps was 4 more than twice the number of postcards
s = 4 + 2p -------- eqn 1
Jason bought both 41-cent stamps and 26-cent postcards and spent $10.28
41 cent = $ 0.41
26 cent = $ 0.26
Therefore,
[tex]s \times 0.41 + p \times 0.26 = 10.28[/tex]
0.41s + 0.26p = 10.28 --------- eqn 2
Substitute eqn 1 in eqn 2
0.41(4 + 2p) + 0.26p = 10.28
1.64 + 0.82p + 0.26p = 10.28
1.08p = 10.28 - 1.64
1.08p = 8.64
Divide both sides by 1.08
p = 8
Substitute p = 8 in eqn 1
s = 4 + 2(8)
s = 4 + 16
s = 20
Thus Jason bought 20 stamps and 8 post cards