Question 771486
Dozen Lemons = x
Dozen Oranges = y
9x + 16y = 1740....1
11x + 20y = 2160....2
Multiply (1) by 11
Multiply (2) by 9
99x + 176y = 19140....3
99x + 180y = 19440....4
Subtract (4) from (3)
        4y = 300
         y = 75.
Substitute y = 75
into Eq(1)
9x + 16y = 1740
9x + 1200 = 1740
9x = 1740 - 1200
9x = 540
x = 60
A dozen lemons cost 60 cents
A dozen oranges cost 75 cents.
Hope this helps.
:-)