Help me with this problem please.

your the problem

Step-by-step explanation:

18

Step-by-step explanation:

A quick way of doing this mentally would be:

1 times 12 = 12

and 1/2 times 12 is the same as half of 12 so 6

6 + 12 = 18

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.