The amount of cocoa powder used in the batter of a chocolate cake and the amount of cocoa powder used in the icing for the cake is in the ratio 5:3. The combined weight of the ICED cake (batter + icing) is 480 g, of which 15% is cocoa powder.

trapezoid

step-by-step explanation:

first i plotted all my points on a grid graph

i made sure all of them were in the correct quadrant

then i saw it was a trapezoid or a quadrilateral

45

step-by-step explanation:

r = 78539458390583095803458309458039485093485 or just 3

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.