ElectricPavlov

Since your Q asks for a graphical solution,...here are the graphs from Desmos.....where they intersect is the solution

Here it is:     tan36 = .72654 = x /15    solve for x

9 * 10 * 10    *  26 * 26 * 26      * 2  

In a right triangle sin S = opposite leg/ hyptenuse

    you will need to use the Pythagorean Theorem to first calculate the opposite leg (RQ)

in a right triangle cos N = adjacent leg / hypotenuse

                                      =   36/ 39       .....and simplify....

bd....

THIRTEEN posts today (at least)....have YOU TRIED to do any of your homework????

*** UPDATE ***     My answer above is incorrect....

1/(A+B) = 6                         1/(B+C) = 9                     1/(C+A) = 12

B = (1-6A)/6                                                                  C = (1-12A)/12

                                             1/ [ (1-6A)/6 + (1-12A)/12]

                                       Solve for   A = 15/216

                                          then       B= 21/216

                                          and        C = 4/216

1/(A+B+C) = x

1/(40/216) = x

    216/40 = x = 5.4 days                    (IF I did all of the calcs w/out error!!)

Yah....you are CORRECT.....had been thinking a bit about that....another answer soon..... bummer !   HaHa

4 out of the 64 are painted on two surfaces

  there are an additional 24 cubes are painted on one side   out of 64

        so 64 - (24+4) = 36 have no paint

so:

\

Bottom   5 x 5

Next level up  6 x 2

Next level up = 5

top = 1                             Add 'em...    this assumes the figure is solid (there are blocks on the lower levels that are not visible)