Answer:
6.67% is as close as you can get
Step-by-step explanation:
The surface area of a sphere is

where r is the radius;
The circumference is

so that

using this value we can evaluate the surface area of 1 ball as:

For 100 ball you get:
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
Answer:
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l______\
Step-by-step explanation: