Step-by-step explanation:
Area of circle:
A=π*(r^2)=π*(16^2)=256π ft^2
Area of the figure:
A=(3*256π)/4=192π=603.185=603.18 ft^2
Assuming you want to choose 4 people from the class of 20;
Begin by using the combinations formula;
20C4=4845 possibilities
Hope I helped :)
Let the full marks be represented by = x
As given, 80% of x is 75
So,

x= 
x=93.75
Hence, full marks is 93.75
We can check also-
=75
Answer: We should order 40 dining room tables type “A” and 90 dining room tables type “B” if we want to minimize our cost.
Please, see the attached files.
Thanks.
Check the picture below
the triangles are similar, the angles are congruents then
so... just add them up, and divide by 2, or set them as rational