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
Answer:
Step-by-step explanation:
The problem relates to filling 8 vacant positions by either 0 or 1
each position can be filled by 2 ways so no of permutation
= 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2
= 256
b )
Probability of opening of lock in first arbitrary attempt
= 1 / 256
c ) If first fails , there are remaining 255 permutations , so
probability of opening the lock in second arbitrary attempt
= 1 / 255 .
This can be solved algebraically. Before we start, as context, to find a percentage you multiply by the percentage/100.

This tells us that 90 is
120% of 75. However, your question wants us to find the <em>increase</em>, therefore we don't need that 100.
Therefore, the increase is
20%.