Question 476465
3.20A + 1.70B = 2*5 = 10

A + B = 5 ==> B = 5 - A ==> 3.2A + 1.70*(5 - A) = 10

==> 3.2A + 8.5 - 1.70A = 10

==> 1.50A = 1.5

==> A = 1 pound for A 

==> B = 4 pounds for B.