To answer, allow the width of the frame to be represented by x. The dimensions of the frame should then be, 11+2x and 6+2x. Subtracting the area of the inside of the frame from the area of the outside should be able to give us 18 cm². The equation,
(11 + 2x)(6 + 2x) - (11)(6) = 18
The value of x from the equation is equal to 0.5. Thus, the width of the frame should be 0.5 cm.
So she divided the 2/3 between 4 friends.
So each friend got 2/3 divided by 4, which gives:
(2/3)*(1/4) = 2/12 = 1/6
