There are two colors of stones in the box ***30 * * * Stone weighs 258 grams, and stones of known colors weigh 1 1 gram every moment.

If there are x big balls and y small balls, there are:

9x+6.5y=395

That is 18x+ 13y=790.

Because:

18= 13+5, 13=2*5+3,5=3+2,3=2+ 1

therefore

1=3-2=3-(5-3)=3*2-5=( 13-2*5)*2-5=2* 13-5*5=2* 13-( 18- 13)*5=7* 13- 18*5

Multiply both sides by 790 at the same time

So 395 = (-3950) *18+5530 *13.

So x0 =-3950 and y0 = 5530 are a solution of the original equation.

X = x0+ 13 * r, y = y0- 18 * r, which is all the solutions of the original equation.

According to the meaning of the question: x & gt=0, y & gt=0.

Solvable: 303.9

So r=304 or r=305 or r=306 or r=307.

Solution: x=2, y=58 or x= 15, y=40 or x=28, y=22 or x=4 1, y=4.