gmattesttaker2 wrote:Hello,

Can you please tell me how to solve this:

If the perimeter of a triangle is 18, then the length of one of the sides CANNOT be:

(A) l (B) 3 (C) 6 (D) 8 (E) 9

OA: E

Is this correct:

The length of any one side of the triangle cannot be greater than the length of the other 2 sides and cannot be less than the difference of the other 2 sides i.e. it has to be

a + b > c > a - b

where a, b and c are the 3 sides of the triangle.

But I was not sure how to apply this here.

Thanks for your help,
Sri

gmattesttaker2 wrote:Hello,

Can you please tell me how to solve this:

If the perimeter of a triangle is 18, then the length of one of the sides CANNOT be:

(A) l (B) 3 (C) 6 (D) 8 (E) 9

OA: E

Uva@90 wrote:

gmattesttaker2 wrote:Hello,

Can you please tell me how to solve this:

If the perimeter of a triangle is 18, then the length of one of the sides CANNOT be:

(A) l (B) 3 (C) 6 (D) 8 (E) 9

OA: E

Is this correct:

The length of any one side of the triangle cannot be greater than the length of the other 2 sides and cannot be less than the difference of the other 2 sides i.e. it has to be

a + b > c > a - b

where a, b and c are the 3 sides of the triangle.

But I was not sure how to apply this here.

Thanks for your help,
Sri

Sri,
What you did is correct,
a + b > c > a - b

If you stuck some where pick from answer and solve it.

for example take 6
if any one side is 6
then can a + b > c pass ? yes it is possible.

Let one side be 9 ,
then a + b > c rule fails,
Hence ans is E.

To the more, Each side of a triangle must be less than half the triangle's perimeter.

Regards,
Uva.

Hello Uva,

Thanks for the explanation.

If we take 1 as the length of a side then we get:

12 + 5 > 1 > 12 - 5

but this won't be valid. Hence, does this rule still apply here.

The same for 3

12 + 3 > 3 > 12 - 3

Thanks,
Sri