The post office sells 2-cent sheep stamps and 3-cent sunset stamps. Jared bought 4 stamps and spent exactly 11 cents. How many of each type of stamp did Jared buy?
2 p + 3 t = 11
but p = 4-t
so
2(4-t) + 3 t = 11
8- 2 t + 3 t = 11
t = 11-8
t = 3
then p =1