Question

Ms. berkin is dividing her 4 1/2-foot by 6-foot bulletin board into 4 sections with ribbon stretched from each corner to the oppsite corner. How much ribbon does she need?

Answer 1

Answer:

15 feet.

Step-by-step explanation:

A bulletin board has been shown in the figure below.

Where the width of the board AB = DC = $4\frac{1}{2}$ = 4.5 feet

and the length of the board AD = BC = 6 feet

As Ms. Berkin is dividing the board by stretching the ribbons to the opposite corners so the length of ribbons will be AC and BD.

In right angle triangle ADC, using Pythagorean Theorem,

$AC^2=AD^2+DC^2$  = $6^2+4.5^2=36+20.25=56.25$

$AC= \sqrt{56.25} = 7.5$ feet

Similarly in triangle BDC,

$BD^2=BC^2+DC^2 = 6^2+4.5^2=36+20.25 =56.25$

$BD=\sqrt{56.25} = 7.5$ feet

Thus, total length of the ribbon used = AC + BD = 7.5 + 7.5 = 15 feet