<span> You refer to a multiple of ten. As a multiple of ten you can just add it to another number easier than a "ones number".</span>
D=Disc
13+10d=83
10d=83-13
10d=70
D=70/10
D=7
7+1=8
Maria purchased 8 CDs. Hope this helps!
All you have to do is multiply 8 by 20 which is 160
Answer:
They are equivalent because they both equal . 8 no matter what because 0's won't matter after the last actual value
Step-by-step explanation:
The formula for a circle's area is
. We are given an area of 38.465 square inches for a quarter of it.
Multiply this value by 4 to compensate for the quarter circle.


Divide both sides by pi (Note: I'm using the conventional value of 3.14)

Take the positive square root of both sides

The radius is 7 inches. Let me know if you have any questions, thanks!