Carcass wrote:
Attachment:
tennis.jpg
Three tennis balls of identical size are stacked one on top of the other so that they fit exactly inside a closed right cylindrical can, as shown.
Quantity A |
Quantity B |
The height of the stack of 3 balls |
The circumference of one of the balls |
Let's examine
Quantity A first
Let r = the radius of a tennis ball
This means the HEIGHT of one tennis ball = r + r = 2r
So, the height of the can = r + r + r + r + r + r = 6r
So, Quantity A = 6r
-----------------------------------
Now let's deal with
Quantity B The circumference of a
ball with radius r = the circumference of a
circle with radius r
The circumference of a circle = 2πr
So, Quantity B = 2πr
-----------------------------------
We have:
Quantity A: 6r
Quantity B: 2πr
Since π ≈ 3.14, we know that 2π ≈ 6.28
So, we have:
Quantity A: 6r
Quantity B: 6.28r
We can see that Quantity B is greater.
Answer: B
Cheers,
Brent
_________________
Brent Hanneson – Creator of greenlighttestprep.com
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