The sum of two numbers is 400. if the first number were decreased by 20% and the second number were decreased by 15%, then the sum would be 68 less. find the numbers after decreasing.

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.

the least common denominator is 40

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.