Hi.Can someone please clarify. The formula for number of scalene triangles with given even parameter is (p-6)^2/48 but it does not hold for p=6. Is this an exception only ? as 1,2,3 is a scalene triangle possible.

Question

Rahul Manchanda · Answer

My bad. 1,2,3 is not a triangle. And for other numbers, we have to take nearest integer not greatest integer.

Deepthi Nagoorkar · Answer

For 7, and 8, it'll be 0. You can even verify it manually, and through the formula.

For p=9, you'll get 0.75 through the formula. Rounded off to 1.

Even if you try manually, you'll get 2,3,4 as the only scalene triangle.

Ritesh singh · Answer

1,2,3 cannot be a scalene triangle as it doesn't satisfy the triangle inequality theorem. For the cases of perimeter as 7 and 9 the formulae changes 
when p is odd (p-3)^2/48

DNS DNS · Answer

You have to add 1 in the solution when p is even multiple of 3.
But still you should cross check with some teacher.

Rahul Manchanda · Answer

Even for perimeter=7,8,9. I am not getting the right answer. Can someone please clarify.

Hi.Can someone please clarify. The formula for number of scalene triangles with given even parameter is (p-6)^2/48 but it does not hold for p=6. Is this an exception only ? as 1,2,3 is a scalene triangle possible.

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