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 =
= 4.5 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 <em>ADC</em>, using Pythagorean Theorem,
= 
feet
Similarly in triangle <em>BDC</em>,

feet
Thus, total length of the ribbon used = AC + BD = 7.5 + 7.5 = 15 feet
The percent change from one period to another is calculated from the formula:
<span><span> Where:<span>PR = Percent Rate
VPresent = Present or Future Value
VPast = Past or Present Value</span></span><span>The annual percentage growth rate is simply the percent growth divided by N, the number of years.</span>
(415.79-200)/200*100=107.89
The annual<span> percentage growth rate is simply the percent growth divided by N, the number of years.</span>
<span>
</span><span>107.89/15=7.193</span>
</span>
5/3 = 1.66667
1.666666^3=4.6296 (Volume is measured in cubic units)
54x4.6396=250
250 x pi = 250Pi.
Speed of current ------ y km/h
<span>distance with the current = 4(x+y) </span>
<span>distance against the current = 5(x-y) </span>
<span>we know that 3.5(x+y) = 70 </span>
<span>x+y = 20 </span>
<span>but 4(x+y) = 4(20) = 80 </span>
<span>then 5(x-y) = 80 </span>
<span>x-y = 16 </span>
<span>x+y=20 </span>
<span>x-y=16 </span>
<span>add them </span>
<span>2x = 36 </span>
<span>x = 18 , then y = 2 </span>
I divided 339 by 6 and got 56.5. That quotient rounded to the nearest whole number is 57. I hope I helped you.