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A circular tabletop is to be cut from a square piece of wood
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10 Dec 2019, 08:05
10 Dec 2019, 08:05
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75% (01:29) correct
24% (01:26) wrong based on 169 sessions
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#greprepclub A circular tabletop is to be cut.png [ 4.82 KiB | Viewed 9199 times ]
A circular tabletop is to be cut from a square piece of wood as shown above.
Quantity A |
Quantity B |
Percent of the wood surface shown above that is not to be used for the tabletop |
25% |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation
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A circular tabletop is to be cut from a square piece of wood
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20 Apr 2022, 11:54
20 Apr 2022, 11:54
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Carcass wrote:
Attachment:
#greprepclub A circular tabletop is to be cut.png
A circular tabletop is to be cut from a square piece of wood as shown above.
Quantity A |
Quantity B |
Percent of the wood surface shown above that is not to be used for the tabletop |
25% |
Let's first assign a nice value to the radius of the circular table top.
Let's say the circular table top has a radius of 1
This means the DIAMETER of the circle = 1 + 1 = 2
This tells us that each side of the square piece of wood must have length 2
Area of the circle \(= \pi (radius)^2 = \pi (1)^2 = \pi ≈ 3.14\)
Area of square \(= side^2 = 2^2 = 4\)
So, the AREA of the wood surface we'll be removing = 4 - 3.14 ≈ 0.86
So, to find the PERCENT of the wood we'll be removing, we must take 0.86/4 and convert it to a percent.
However, since we already know that 1/4 = 25%, we can be certain that 0.86/4 equals some value less than 25%
We have:
QUANTITY A: some value less than 25%
QUANTITY B: 25%
Answer: B
General Discussion
Re: A circular tabletop is to be cut from a square piece of wood
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14 Dec 2019, 02:56
14 Dec 2019, 02:56
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Let Side of square = a
Radius of circle = r --> a = 2r
area of square - area of circle
4r^2 - (pi)r^2 --> (pi = 3.14 approx)
= 0.86r^2 --> A
25% of area of square = (1/4)4r^2 = r^2 --> B
B is greater. Hence, B is the Answer.
Radius of circle = r --> a = 2r
area of square - area of circle
4r^2 - (pi)r^2 --> (pi = 3.14 approx)
= 0.86r^2 --> A
25% of area of square = (1/4)4r^2 = r^2 --> B
B is greater. Hence, B is the Answer.
