How to do surface area of a triangular prism

651.6

Step-by-step explanation:

surface area = b h  +  2 l s  +  l b

b= base h= height l= length s= side

or

find area of all the parts and add together

10

step-by-step explanation:

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.