Answer:
The area of the wrestling ring is 5.29π 
Step-by-step explanation:
A sumo wrestling ring is circular and has a circumference of 4.6π meters.
To find its area, we need to first find its radius.
The circumference of a circle is given as:

where r = radius
Hence, the radius of the ring will be:

The radius of the ring is 2.3 m.
The area of a circle is given as:

Hence, the area of the wrestling ring (in terms of π) will be:


The area of the wrestling ring is 5.29π 
Answer:
Davide's age is 10.
L'età di Davide è 10.
Step-by-step explanation:
The average age of Aldo, Bruno, Carlo and Davide is 16 years.
I am going to say that:
x is Aldo's age.
y is Bruno's age.
z is Carlo's age.
w is Davide's age.
Average of the 4 is 16 years.
This means that:


If we do not consider Davide, the mean is 18. So


Replacing in the first equation:



Davide's age is 10.
L'età di Davide è 10.