8 balls = 16
1 ball = 2
32 balls = 64
$20-$14.56=$5.44
The mechanic would get $5.44 back as change.
Simplifying
30c + -45d
Factor out the Greatest Common Factor (GCF), '15'.
15(2c + -3d)
Final result:
15(2c + -3d)
If the radius of the circle is 4 than the area would be 50.27.
If you are saying that 4 is the diameter, than divide that by 2 to get the radius which is 2. The area for this would be 12.57.
I don’t know which one you mean but hope this helps :))