Answer:
39.60
Step-by-step explanation:
9.90 x 4 = 39.60
You can use it to find the area of something
Answer:

Step-by-step explanation:
We need to find 1/4 of the area of a circle with a radius of 8
Let r be radius
Area of a circle = 
Substitute r with 8
Area of a circle = 
Now, to find 1/4 of the area, we can create an equation 
The answer is 
Hope this helps :)
Have a spectacular day!