Answer:
The first step on this case is order the dataset on increasing way, and after do this we got:
11 14 15 16 17 17 18 19 21
We have a sample size of n =9
And in order to find the 75th percentile we need to find the position for this percentile with this formula:

So then we can conclude that the 75th percentile would be approximately on the 7 position of the dataset ordered and we got:

Step-by-step explanation:
For this case we have the following data:
16 17 11 21 15 14 17 18 19
The first step on this case is order the dataset on increasing way, and after do this we got:
11 14 15 16 17 17 18 19 21
We have a sample size of n =9
And in order to find the 75th percentile we need to find the position for this percentile with this formula:

So then we can conclude that the 75th percentile would be approximately on the 7 position of the dataset ordered and we got:

X=angle
x+(10/9)x=(19/9)x=76
x=(76*9/19)=36
First rectangle:
Has 3 cubes in each 5 layers, and imagine it, so we have all dimension needed which is:
l=3 unit
w=1 unit
h=5 unit.
V=l×w×h
V=3×1×5
V=15 cubic inches.
Second rectangular:
Doing the same like that to get:
l=5 unit
w=1 unit
h=3 unit
V=15 cubic inches. As a result, there are no prism that are greater to each other, which mean that they have the same volume of 15 cubic inches. Hope it help!
Answer is 13.75 inches for each side of the square board
Step by step
A square with an area of 189 in sq. , take square root of 189 = 13.75 inches