SHRUJAL
DongminShin
Two questions here for those who thinks the diagonal is the radius of the circle and for those who solved this problem by dividing the choices by 12.
1. Apparently, the vertex of rectangle is not touching the quarter circle's line. But how can you tell the diagonal of rectangle to be the radius of the circle?
2. There is no any condition stated in the question that the height of rectangle need to be integer. But how can you conclude that (D) is the answer, only because (D) 192 is divisible by 12?
For the second point ,
Area = L*B
Area must be divisible by L and B
So , even if the width is not an integer
Suppose , Width = 10.5 , length = 12(as given)
Area = 10.5 * 12 = 126
If you divide ( Area / Length) , you will get the breadth . i.e (126/12) = 10.5
Please remind that I don't have any intention to make you feel bad,
but I need to tell you or other people who thought (D) is the final answer only because 192 is divisible by 12 that
YOU'RE APPROACH IS WRONG.
Let me first repeat that the length of rectangle can be any kinds of real number. It could be an integer or an integer.
Based on your approach, 192 is the final answer, because 192 is 12 *
16, where 16 is an integer.
But according to your approach,
why not the length be
172/12? so that it could make the area to be 172?
why not the length be
178/12? so that it could make the area to be 178?
why not the length be
186/12? so that it could make the area to be 186?
why not the length be
198/12? so that it could make the area to be 198?
It seems that you didn't get my point at all.
Area is a product of the
length(l) and the width(12).
But there is no any condition stated that length should be an integer.
That will mean that the length does not necessarily need to be an integer. It could be any real number.
Assuming that the diagonal of rectangle is not touching the quarter circle's line.If you apply the Pythagorean theorem by yourself, you are gonna know that the length of rectangle should be less 16 since the diagonal is shorter than radius.
And at that point, you would be able to narrow your answer options from (A) to (C), NOT (D) and (E).
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The reason of choosing (D) as an answer should be only because you assumed that the diagonal is touching the quarter circle's line. At the same time assuming the picture is drawn incorrectly.
But the reason of choosing (D) as an answer should NOT be because you thought the length should be an integer which makes the 192 divisible by 12.