Question 260702
This is a mixture problem. Here is a table based on the above information.
tea . . . . . . . . . . . . .$/lb . . . .. . . . . . lb . . . . . . . . . . . $
A . . . . . . . . . . . . . .($3.45) . . . . . . . x . . . . . . . . . . . ($3.45x)
B . . . . . . . . . . . . . .($2.15) . . . . . . . 80-x . . . . . . . . .$172 - $2.15x
mixture . . . . . . . . . ($2.75) . . . . . . .80 . . . . . . . . . . .$220
First, the variables x and y are there to confuse you. You only need x.
using the third column we get
(i) {{{3.45x + 172 - 2.15x = 220}}}
combine like terms to get
 (ii) {{{1.30x + 172 = 220}}}
subtract 172 to get
(iii) {{{1.30x = 48}}}
divide to get
(iv) x = 36.92
you need ~ 36.92 lb of the $3.45 tea and ~ 43.08 lb of the $2.15 tea.
these are unusual answers, but they work.